the 7 1/4 Sure Grip deserves the bad rap I think, I had a 72 Duster and the stock 318 2bbl proved too much for it. For an A-body you can't beat the 8 3/4.
@@bottomshot4546 I have one of each for my 67 Barracuda. We'll see what the high lift 360 does to the 7 1/4 first. Just have to find time to get the brakes on it.
I used a 8 3/4 Mopar under a 81 Malibu wagon that was powered by a 680hp 477ci Rat. Never broke it. Ended up swapping it into a 79 cutlass with a 600+HP Olds engine. Good rearend really.
Cut and dried. I have a 7.25 and everybody says lose it and go bigger. Im runnin it. Got a chuckle from sure grip or posi. Keep it up! Old school rules’ Guess you are old school’in.
I'm running a D35 non c-clip, trussed with u-bolt eliminators and homemade caltrac. About 160 Canadian rubles and a weekend. Also just added an LSD. This heep just leaves, even on shitty old dealer donuts. Held up to 360+hrspwers for the last 8 years. Gonna put together a snailcharger setup and aim for 500-600HP and see how well this turdy5 will hold together lol.
Uncle tony! I love your videos, I showed them to my dad who loves your videos also, he’s very old school and loves his classics and sticks to the same principles you do about how he treats his cars. It’s great to learn from a no bullshit Kinda guy.
Back in the late 70s and early 80s we used to pick up the full size beasts for cheap to abuse them for fun .We had a 75 Gran Fury police pursuit with the Dana and sure grip . It was great for digging / melting twin trenches in fresh asphalt along with some off roading without breaking a sweat. I also had a couple 73 LTDs with traction lok 9s that took a lot of abuse including a Country Squire that could haul like a F-250 .Never had an issue with the rear but the C6 stopped moving forward . I tore it down and found all the teeth on the forward clutch plates were stripped off even though there was still plenty of friction material on the plates and nothing was burned.
Nice video Tony. I bracket raced a 60s front engine dragster with my 'boys' up close to an 8-3/4, and worked on a twin engine injected fueler that also had an 8-3/4. I had good luck with them in my 340 Swingers too.
I had an 8 3/4 in my '70 383 (rebuilt hot 383) Super Bee with a reverse valve body 727 & B&M slap stick shifter (originally it was a pistol grip 4 sp) and it performed just fine.
The 8 1/4 rear end is pretty good. The problem is if you want to race it at the track, the NRA rule book has a thing about C-clip axles. Same with the 9 1/4. About 3 decades ago, I swapped the 7 1/4 that was in a '74 Dart Sport I bought with an 8 1/4 with 3.55 ratio. It was originally a 6 cyl car, but the neighbor's high school kid put a 318 in it. The engine was "rebuilt" at the high school, but it was a mess. After redoing it, the car was a blast!
Thanks for the Lesson. A month ago or so I researched my D100s rear end (8-3/4) and was surprised at how many people liked that rearend for all sorts of stuff. I liked hearing in words instead of reading between forums....sort sweet simple! Maybe you could lead me to a R and R video for that rearend (68) my seals are shot
Good info, Tony. My 68 & 69 340-S Barracudas came w/ small/straight pinion 8¾" rear axles w/ Sure Grip differentials. The '68 (w/ 4-speed) is setup for ET bracket "drag": racing (3000#, low 11s) w/ 4.86:1 cogs + spool + aftermarket axles. The 8620 alloy x 1.75" gears last about 5 full seasons before they go "BANG". The axles last about that long before twisting. I burned up a coupla early PowrLock-style differentials before stepping up to a spool. :) My '69 Barracuda CV is a street car. I found a 3.55:1 pumpkin w/ late Sure Grip. The crush sleeve that sets the 1.875" tapered pinion bearing preload failed about the same time the Auburn (GM-style) differential failed. I replaced the crush sleeve w/ a spacer (Ratech #4103). I replaced the differential w/ an early PowrLock unit I had. Because the clutches are preloaded, powering thru a tight corner is "more interesting" but, unlike the later Auburn unit, it'll last longer, and is more efficient. :)
Again another great program thank you Uncle Tony really enjoy your show very informative and straightforward as usual hang on to that cigarette buddy don't lose it
I liked this.. actually have a 99'-04' 8.8 setting aside for my 69'Satellite now. Seemed to be my best path as I have ALOT of parts setting around for them and I intend to go the Calvert Racing route with the ass end.
I LOVE your "one size does not fit all" mentality. So many people get into the "this is best regardless" mode and it's impossible to reason with them. My fox is getting an 8.8 out of an SN95, with C clip eliminators and a spool. It'll stay that way until I hit enough power that it's breaking, or I decide I want to keep a few center sections built for different conditions (1/8th, 1/4, street). The goal of the car really isn't a street car, but I'm not starting out with huge power and a trans brake - but that'll be in the works - which is probably when the 8.8 stops being the right one - for ME.
Apparently I"m binge watching your channel on this rainy Northeast day Uncle T :) Very true about the Dana 60 with 4.10 gears I put under my Duster --strong diff but heavy...
It depends on which you are comparing to what . 8 3/4 center section was stronger than the gray-iron ford. The clutch suregrip was better than ford's limited slip, the 30 spline axles were bigger and stronger than the standard ford 28 splines. BUT! Ford also had stock in certain models, nodular iron center sections, just as strong as the 8 3/4, probably stronger, a detroit locker was available, bunches stronger thana cone suregrip, 31 spline axles, bigger and stronger than the 8 3/4, and the bigger hypoid angle that tony talks about as a liability, also results in longer, larger teeth and more tooth contact area, which means the 9 inch has stronger gears than the 8 3/4 anyway, much more than just the 1/8 inch gear difference would indicate. 8 3/4 is a fine rearend, ive got one in my eleven second mopar. But ive got a nine inch in my eight second car.
Nice info Tony! Simple and informative. I remember a lot of guys talking about the ford 9inch but had no idea it was harder to turn and that the pinion was set lower for strength. Good stuff!
The Fomoco 8.8. So glad you gave this props. And even a shoutout to the Explorer. Im ashamed to admit, but the Exploder is actually my favorite truck. So versatile, not to mention parts for them grow on trees.
It’s me, you invited the comments so: nothing says I’m stronger than death than constantly having a smoke in your hand. I love the content and the invite to smartassery , woopwoop
I got a 8 inch Ford rear end in my cougar right now and while it did explode on me. It has treated me fair on gas mileage and reliability. Just gotta make sure it has oil in it is all. Damn wheel seal went out and I didn't notice till 50 miles from home.
I met a guy at an NHRA national event running an 86 Malibu with a big block Chevy. He was running low tens and lifting the front wheels in first and second. Beautiful car. I looked under the back of the car and he was running a 7-1/2" ten bolt. I asked him about and he just held up both hands with his fingers crossed and said "I'm on my second season. No problems yet' Never would have believed it if I hadn't seen it myself.
The 8 3/4 rear end is a great differential. The one thing you'll want to do to make your life easier is to use Green bearings retrofit axle bearing. The original bearing have to have the tension on the bearing set, but not so with the green bearing. This lets you swap center sections easily, so you can run3.55's or higher gears in the street and swap in a set of 4.30's with positraction on the weekends. My friend would haul a small trailer with him to the track which held his slicks, front runners and strip gears to the track. Whenhe got there it was a fairly simple swap to make, except catching the gear oil and pumping it back into the differential once the center section went back in. The only problem with this trackside surgery is dust, and gears and bearing don't do well with dirt in the oil, just like your engine. So, if your track has a paved pit area this might work for you. If not, you may want to go dressed for battle!
Thanks for the great new info - always learning. Didn't know that about the 9" Ford rear Vs the 8 3/4. I didn't realise the 7 1/4 was that good. I had a 71 Challenger 318 H price code Slapstick auto with one of these in it and was surprised to see that - unless someone swapped it out at some stage - will never know. But it had several chunks of metal from the crown wheel floating around in it and it was only a totally stock smog 318. Next video coming up is the one on pinion snubbers!
i can remember well, back in the day. you,d see just as many 8-3/4s at the digs as 9 inch fords. i saw alot of oldsmobile pumpkins too. kool that you always consider parasitic horsepower dragdowns because its huge. big daddys got smokey yunicks old custom made device through gm. an electric power-source that spins a non-fired motor. measures down to how many horses internal friction[s] consume, then each supplemental and sequential you bolt up afterward, tells you crazy things like how many horses the oil pump requires, or the drag of different timing chains...no wonder smokey was known to "wring out" every last available horse out of his engines, garlits says hed work weeks for even 1 more horsepower...far out....a lincoln versailes is a great swap for street or mild to light race duty, if you can find 1...mildly narrow width...9 inch...traction-lok diff....disc brake setup....a 10-bolt chev is a little stronger than people think, if you eliminate the c-clips, and i think the poncho is the strongest 10 of the generals and can work ok for street/street tires...i also remember seeing many, many 6-cylinder firebirds during servicing that had 10-bolt posis in em factory, why... i do not know.
Okay... I listened to and (89%) understand your explanation, it makes sense. I see *way* too many people go for Ford 9s or D60s because "They're the best, bigger's better!" Though they're under powered & can't get them to work to their potential, all of them subsequently complaining about "traction issues" or dogging or "weirdness" off the line, etc. and immediately leap down rabbit hole after rabbit hole. 🕳 😊 That said... Here's the back story of my ride so you (and/or another viewer) may possibly, properly (hopefully) answer my question(s) and keep me from going off track (see what I did there? 😊). This is a bit of a different, progressive build so, I'm a "more info is way better than no info" kinda guy when seeking help. 😉 I'm in a stock bodied, '74 Road Runner, running a 440 magnum with a cam, about to get the heads reworked for "happy flow" (nothing stupid, massage the valve bowls for equity of volume, open/polish the runners, compound valve seat cuts, etc.. For now. I'm also undoing *a lot* of mistakes that someone before me inflicted upon this thing. The trans is being properly built and re-valved for what I need and, I'm losing the carbonator (someone put a Holley double pumper on a single-plane manifold, leaving a nice hole in the power curve) and adding a full, Pro Flow 4, SMPFI system with a fuel sump to eliminate starvation, start *when I want* and achieve the best possible fuel usage. This also lends itself to (one day) putting a nice, Paxton "hat" on top of its handsome, little head. 😊 So, the power is coming, eventually. But I'm still not going for a 1,000+ HP monster, just a healthy 5-600 or so, allowing that 4k lb. sled to get out of its own way and, maybe even surprise a few people... And this is where the questions start, trying to get the most effective suspension/rear end setup to effectively take advantage of the power on hand. In the meantime, it's just a naturally aspirated, unbored, unstroked, 440 magnum plant so, it's not generating crazy amounts of power. It's got a 3.91 gear that someone put in the rear, not understanding that it won't work with the (now cooked and currently being rebuilt) 3spd. transmission. I actually want to keep the lower rear gear for those "special occasions" so, I've ordered a Gear Vendors double overdrive unit for it. This will give me a 3.03 final drive for cruising the highway and not chewing through every gallon of gas within a hundred mile radius. (Pretty slick, eh?) The gears sit in an 8 3/4" rear. It's time to replace the worn, factory springs and add some urethane bushings to keep everything happy but, I'm not sure if I'm better off staying with the current style, leaf spring set or going mono-leaf and, if running a Cal Trax set-up is worth the $$/effort or, do something altogether different. I'm building a street/strip cruiser that's definitely more street than strip but, whether I'm "street fighting" or going out for a true, "strip adventure," I'd like to find the combo/compromise that will give me the best balance overall. Although I understand the basics, I'm not personally experienced with mono-leaf springs and the Cal Trax system so, given what I'm driving, which way would you go and what tips for "tweaking" it do you suggest?? Thanks for taking the time. 😊
Thank you for this uncle tony. I have a 8 1/4 in my mopar and have been thinking about swapping it for a Dana for a while but don’t wanna fork over that money. I’ll just keep my 8 1/4
The 7 1/4 is great if you don't pile a bunch of power on it. I still can't believe how long mine held up. Tony sure knows his stuff...the spider gears are often cringe-worthy when you pull the cover. I like how this channel covers what most others don't know and pass off as irrelevant.
I like dropout third members and have an 8 and 3/4 in my hotrod...It had a broken cap and I had billet steel caps installed by Mark Williams...Also a crush sleeve eliminator too...Ford had straddle mounted pinions back to 1933...In fact I think the 9 inch Ford uses the same bearing...
The pinion being on the bottom of the case and ring gear also causes them to break off at the pinion (spit the pinion) and destroy the underside of the car when the driveshaft throws it around lol. The 8 3/4 is (in my opinion) superior to the 9 inch
Maybe I’m a nerd, but I can’t bring myself to run anything smaller than a 1.5 x 35 spline axle. I only play with big blocks & I’m done breaking stuff. I’ve noticed that the 14 bolt GM axle & the Ford 9 inch both use a 3rd pinion bearing & I think that has more to do with a pinion housing that is not cast into the differential carrier. With that said, I’ve never had an 8 3/4 fail
Danas are way heavier than 9 inchers though.. it's just a better choice, because theyve been the go-to diff for so long, theres so much support and you can buy aftermarket everything for them. gauranteed if you break down in a small town usa, you can find the bits to getyou going at the local autozon e. Hey you can beef that 8.75 housing up by welding gussets of 3mm steel from the top of the pumpkin folded to same width and out about 4 inches tapering back into the axle tubes.. julst copy the pictures on the strange engineering website ;)
TONY, THE NINE INCH IS LEGENDARY. IT IS THE STRONGEST AND LIGHTEST. A 9" HAS THE PINION SUPPORTED ON THE END UNLIKE THE DANA WHICH DOESN'T. BUT IT'S TRUE STRENGTH COMES FROM THE RING AND PINION CONTACT POINTS ARE ON 3 TEETH AS OPPOSED TO THE DANA THAT CONTACTS ON 2 TEETH. THE 3 TEETH CONTACT POINTS IS A LITTLE KNOWN FACT OF WHERE THE FORD TREMENDOUS ABILITY TO HOLD POWER COMES FROM.
Tony, I have to disagree with you about the 7 1/4. After I replaced the 170 Slant Six in my '63 Valiant with a 180 HP 273/4 speed, it didn't take very many speed shifts and power shifts to destroy those spider gears. I went through a couple of rear ends before I grew up and started going easier on the shifts. Dumb me, I should have gone with the rear from that Barracuda that donated the engine and trans!
Awesome Uncle Tony《☆》My 73 Dart Sport 360 auto has a 7-1/4 suregrip. It was fine till I put a bigger carb & 15" cop car wheels on it. A few hard launches & it spit a bolt thru the rear cover. Luckily Mopar performance sells a ring gear bolt kit for them. Not sure how well it works yet but I'm going to give the 7-1/4 another shot when I finish up a zillion other items on the old rust bucket🤠☻🤠
@@UncleTonysGarage 《☆》Thanks :*: I will definitely forewarn the future owner. I'm also concerned with rust issues like the rain rails & subframe so it may just wind up being a running parts bin 😖☻🤠
The new 8.8" f150 and 9.75" f150 diff 2015 and up are strong as hell also and also have factory disc brakes. The junkyards will be full of them and the 9.75" is VERY similar to a D60
I rebuilt my 8.25 Chrysler diff. It wasn't that difficult to do. First I started trying to tighten up the backlash to get rid of the clunk it had because of all the mileage, but that caused a vibration. I could not get it within specs. 4- 10 thou or something like that. It wore a bit egg shaped or whatever. So I drove it for a few months to work and back, all city driving, and it began to smooth out, and I thought it would work, but then I had to take a 3000 mile round trip on the highway and it did not get better. The vibration got worse, so I ordered the new parts for a rebuild, and right after the rebuild, on the test drive, though the vibration was better, it was really still there. So what happened was that what started out to be vibration from the out of spec diff that I tightened up, though it began to improve in smoothness, the other parts were taking a beating and began to cause their own vibration, and I was fooled by this. So I ended up replacing both u-joints, a transmission tail shaft bushing, motor mounts and transmission mount, in addition to the diff rebuild, but wow! Smooth as heck now, and almost 2 mpg improvement, too. Like new, in the back anyway. So I know what having a 1/2 new van feels like, anyway. 530,000 or so miles on it now, but man is it smooth going down the road. A pleasure to drive, yet.
Yeah its like the 7.5 ford diffs. some say they are weak as hell but really they are pretty good. Again the spider gears are the weak link. Put a Auburn lsd diff in there and a stud girdle good for 450hp.
those 8.8 fit nicely in my S10 V8 u get posi trac disc brakes and very little customizing just a hole or 2 to expand, brake hose adapter and change bolt pattern or just run ford wheels
The pinon nut came loose on my 67 one day driving it,,,,4 spider gear sure grip,,,4,10 ..the nut was captured in the u joint,,,i had to keep it loaded up so the pinon gear would not slip back and make bad noises....just had to replace the pinion seal,,witch is made of leather,,,,,good times
I'm Building a street strip Squarebody (mainly street). I'm building off a GM 10 bolt 8.5. Gonna do a 4.11 8.6 ring gear with a 30 spline axles to give it a fighting chance. Probably going to get a Eaton Truetrac. Got a 700r4 Overdrive trans so I figure 4.11s will be alright going done the highway.
Hey Uncle Tony, love your vids! I'm kinda new to Mopar, but I'm building a '66 barracuda with a 318 2bbl, A833 od tranny. All the old timers tell me the 7. 25" won't last. Any thoughts on how I can make it live longer? The engine is bone stock other than headers
Im planning on putting a 9 inch in eventually, but I'll just keep an eye on the spider gears. Maybe even use some synthetic lube. Thanks for the input. Keep up the awesome work! You're the best!
Now that 8.75 third is bomb proof from that era. The housing is easily trussed and tons of after market support. However, today their a hard find or folks want big dollars.
The 57to 64 Olds 9.3 is one of the stronger OEM rears but getting scarce and pricey to build. Very similar to the 8&3/4 and 9in Ford.Thinking of having one built for a 67 olds442 but it will cost some serious money.
For a car these may great, for me dealing in pickups and bigger even that 8.8 or 9inch is small and weak.. Just think a ford 9 inch in the back of my f600... :) snap..
What's the opinion of the Chrysler 9.25? sorry if i missed this earlier in the comments. What kinda power can it handle, weak points like shock load ect.. @Uncle Tony, I'd love to keep learning about the 3rd gen Hemi and what a recommended budget upgrades for top and or bottom end. Especially for something like my 05 Ram.
I screwed up I had a 8 3/4 sure grip in my barracuda FS with 392s and I put a tall tire so it made it around a410 gear that car launched fucken awesome at the strip
What I hate is when you're working on something and you don't think the process through thoroughly. At this point you either break something or loose something and say why did I do that. Good example I was replacing the u joints on my 84 Corvette. I was greasing it up and the one cap popped off spilling the bearings all over the floor. I cleaned everything up and counted 27 bearings and the one that didn't fall off had 32 bearings. Where did the 5 bearings go I ask myself. Fortunately I work at an auto parts store so I get a discount on another one,but it still ticks me off. What I need is the comonsense angel tapping on my shoulder saying I wouldn't do it that way.
Did you ever notice all the guys at NASA always had a fag hanging out of their mouth, great stress reliever, get ready to launch a rocket ship to space or drag race a car down the strip figuring out the best rear end set-up, 🔥 fire up one of your favorite brands, go Uncle Tony🏎️🏁
I much prefer rear ends with the removable pig so all the lash can be set up on a workbench. Packard is the automaker responsible for the helical ring and pinion for quieter running with the pinion low to lessen the clearance needed for the driveshaft while Ford continued with beveled gears a few decades longer.
So true...the 7.25 is like the Slant Six and 318... Automatically discarded and/or underappreciated... I had a 7.25 wirh 2.69gears in my 68 Dart. I was working on narrowing some 8.75 for it but never finished. In spite of what people said, that rear survived 2.5 years of daily driving and weekend strip action behind a 440/727 that pushed it to theb11.50s in spite of the ratio. It was still goin strong when i sold the car.. So i wouldnt be afraid to run one for a while til you can upgrade it guys...
Really? I have always heard if you spin them they will snap i have a suregrip or limited slip in it s6 to v8 swap 2.96 rear ratio 7.25 im deathy afraid ill snap it with the first year 318 high performance 4bbl one i have in it 1968 mopar 318 4bbl rated at 230hp and 340 lb of torque has high lift rv cam so probobly a lot more torque
@@timallred6789 Yeah...i mean, the consensus is that theyre weak. But maybe not quite as bad as everyone thinks. I was told itd explode first time I fired up the 440!! (It ran strong too with 10.2:1 comp, .484 MP cap, ported heads, M1 single plane, etc) but it lived for about 40k miles and right around 100 1/4 mile passes. Never broke or sprung a leak. I never even changed oil in it cuz I thought itd blow...but it never did!!!!
wow living behind big block power I am amazed. In my limited experience, the 7 1/4 sure grip in my stock 318 2bbl 72 Duster grenaded after maybe 2 years of street driving, just my 'get me to school ride', took it down the strip a time or two but nothing too crazy. The spiders each had one or two teeth left on each gear.
Yo Tony love you videos thank you for all the Information That you give us I need some help Please I have 1976Dodge Dart Swinger Slant 6 I am going to put a V8 in it Need help On What kind Of rear end Should I go with Don't have Lots of money So Looking Maybe Picking Up something At a junkyard or Secondhand Please Throw me bone Would be very happy😃If you can help Me out Thanks Tony You're the man
Back again Tony! My setup is a 70’ challenger 225. Looking to drop a rebuilt purple cam 318 paired with a A833 OD… it currently has the 7-1/4 in it right now, would you upgrade to a 8-3/4 2:76? My Plans for the car : Grocery getter, cruiser .
I’m about to throw an 8.8 under my first gen Charger. I’d keep the 8 3/4, but for less than a sure grip center section, I’ll get decent gears, an LSD, 31 spline axles and disc brakes by pulling an entire Explorer rear end. Same wheel stud pattern too. What’s not to like?
Hey uncle Tony !! Im been binge watching your videos this evening . I just ran across this video and I thought Id ask you about something. I jave a '83 b250 van I been messing with for about a year. Ive been thinking about doing something with yhe transmission so I could end up with overdrive. My first thought was a gear venders unit. Of course those are a bit pricey. My next thought was to get a transmission out of a dakota with a 318 I haven't looked too deep into it yet but, I will soon. That era of mopar transmissions amd their reliability issues make me nervous though. Thinking about the trans leads me to the rear end. I have a 91/4 and I dont know much about it. What is your opinion on that rear end ? And, what is your suggestion for getting overdrive into my van? I use this van to travel with my wife and 2 kids so I want to do something thats bomb proof. My van has a 318 with what I believe to be a 904 transmission.
Honestly, overdrive automatics are something I have very limited experience with, so I can't really give you a quality answer to that. As for the 9.25, they are extremely stout rears, but have been known to shred spider gears at random times.
The distinct lack of bullshit on this channel is why it's my new favorite. First nice thing I've ever heard about a 7 1/4. Please keep these vids up!
the 7 1/4 Sure Grip deserves the bad rap I think, I had a 72 Duster and the stock 318 2bbl proved too much for it. For an A-body you can't beat the 8 3/4.
@@bottomshot4546 I have one of each for my 67 Barracuda. We'll see what the high lift 360 does to the 7 1/4 first. Just have to find time to get the brakes on it.
bottom shot blew one up with a auto slant
Amen on the 7-1/4!
I agree :)
2:00 I love this guy, "the occasional smoker" he smokes in all positions. Under gas tanks, in hurricanes etc.
Lol
Man I’m so glad to have found this channel there’s just not any good old knowledgeable mopar guys that will teach. Thank you uncle Tony.
I used a 8 3/4 Mopar under a 81 Malibu wagon that was powered by a 680hp 477ci Rat. Never broke it. Ended up swapping it into a 79 cutlass with a 600+HP Olds engine. Good rearend really.
Uncle Tony is the best .. and I'm strictly a ford guy and specialize in 60's and 70's fords almost exclusively.
Haven't been subbed to Tony's channel for a week, and already learned all kinds of stuff. Awesome.
Richard Petty ran the 8 and 3/4 because it was strong and you could change gears fast.
Important when you went to different tracks all the time.
Cut and dried. I have a 7.25 and everybody says lose it and go bigger. Im runnin it. Got a chuckle from sure grip or posi.
Keep it up!
Old school rules’
Guess you are old school’in.
I'm running a D35 non c-clip, trussed with u-bolt eliminators and homemade caltrac. About 160 Canadian rubles and a weekend. Also just added an LSD. This heep just leaves, even on shitty old dealer donuts. Held up to 360+hrspwers for the last 8 years. Gonna put together a snailcharger setup and aim for 500-600HP and see how well this turdy5 will hold together lol.
Uncle tony! I love your videos, I showed them to my dad who loves your videos also, he’s very old school and loves his classics and sticks to the same principles you do about how he treats his cars. It’s great to learn from a no bullshit Kinda guy.
Best videos on muscle cars I have seen.
Short sweet and to the point. I like what you do here.
Thanks for defending my tiny rear diff on my Slant6 68 Dart and my 318 68 Dart.. always awesome Uncle Tony.. thanks
Back in the late 70s and early 80s we used to pick up the full size beasts for cheap to abuse them for fun .We had a 75 Gran Fury police pursuit with the Dana and sure grip . It was great for digging / melting twin trenches in fresh asphalt along with some off roading without breaking a sweat. I also had a couple 73 LTDs with traction lok 9s that took a lot of abuse including a Country Squire that could haul like a F-250 .Never had an issue with the rear but the C6 stopped moving forward . I tore it down and found all the teeth on the forward clutch plates were stripped off even though there was still plenty of friction material on the plates and nothing was burned.
Nice video Tony. I bracket raced a 60s front engine dragster with my 'boys' up close to an 8-3/4, and worked on a twin engine injected fueler that also had an 8-3/4. I had good luck with them in my 340 Swingers too.
Tony I love mopar grew up in a mopar family these videos are great.
Never had a problem with an 8 3/4 Chrysler outstanding build.
Been wanting to dig into this topic!
I had an 8 3/4 in my '70 383 (rebuilt hot 383) Super Bee with a reverse valve body 727 & B&M slap stick shifter (originally it was a pistol grip 4 sp) and it performed just fine.
The 8 1/4 rear end is pretty good. The problem is if you want to race it at the track, the NRA rule book has a thing about C-clip axles. Same with the 9 1/4.
About 3 decades ago, I swapped the 7 1/4 that was in a '74 Dart Sport I bought with an 8 1/4 with 3.55 ratio. It was originally a 6 cyl car, but the neighbor's high school kid put a 318 in it. The engine was "rebuilt" at the high school, but it was a mess. After redoing it, the car was a blast!
Thanks for the Lesson. A month ago or so I researched my D100s rear end (8-3/4) and was surprised at how many people liked that rearend for all sorts of stuff. I liked hearing in words instead of reading between forums....sort sweet simple! Maybe you could lead me to a R and R video for that rearend (68) my seals are shot
Your axle seals are shot on a 8 3/4 or is it the pinion seal?
Good info, Tony.
My 68 & 69 340-S Barracudas came w/ small/straight pinion 8¾" rear axles w/ Sure Grip differentials. The '68 (w/ 4-speed) is setup for ET bracket "drag": racing (3000#, low 11s) w/ 4.86:1 cogs + spool + aftermarket axles. The 8620 alloy x 1.75" gears last about 5 full seasons before they go "BANG". The axles last about that long before twisting. I burned up a coupla early PowrLock-style differentials before stepping up to a spool. :)
My '69 Barracuda CV is a street car. I found a 3.55:1 pumpkin w/ late Sure Grip. The crush sleeve that sets the 1.875" tapered pinion bearing preload failed about the same time the Auburn (GM-style) differential failed. I replaced the crush sleeve w/ a spacer (Ratech #4103). I replaced the differential w/ an early PowrLock unit I had. Because the clutches are preloaded, powering thru a tight corner is "more interesting" but, unlike the later Auburn unit, it'll last longer, and is more efficient. :)
Again another great program thank you Uncle Tony really enjoy your show very informative and straightforward as usual hang on to that cigarette buddy don't lose it
This video is exactly why I subd Tony your a wealth of knowledge thanks
I liked this.. actually have a 99'-04' 8.8 setting aside for my 69'Satellite now.
Seemed to be my best path as I have ALOT of parts setting around for them and I intend to go the Calvert Racing route with the ass end.
I’ve been working on cars and engines since I was a kid with my dad. Every video I’ve learned things !
I LOVE your "one size does not fit all" mentality. So many people get into the "this is best regardless" mode and it's impossible to reason with them. My fox is getting an 8.8 out of an SN95, with C clip eliminators and a spool. It'll stay that way until I hit enough power that it's breaking, or I decide I want to keep a few center sections built for different conditions (1/8th, 1/4, street). The goal of the car really isn't a street car, but I'm not starting out with huge power and a trans brake - but that'll be in the works - which is probably when the 8.8 stops being the right one - for ME.
Apparently I"m binge watching your channel on this rainy Northeast day Uncle T :) Very true about the Dana 60 with 4.10 gears I put under my Duster --strong diff but heavy...
I read in a old Hot Rod magazine article that the 8.3/4 in stock form was stronger than a 9 inch ford.
It depends on which you are comparing to what . 8 3/4 center section was stronger than the gray-iron ford. The clutch suregrip was better than ford's limited slip, the 30 spline axles were bigger and stronger than the standard ford 28 splines. BUT! Ford also had stock in certain models, nodular iron center sections, just as strong as the 8 3/4, probably stronger, a detroit locker was available, bunches stronger thana cone suregrip, 31 spline axles, bigger and stronger than the 8 3/4, and the bigger hypoid angle that tony talks about as a liability, also results in longer, larger teeth and more tooth contact area, which means the 9 inch has stronger gears than the 8 3/4 anyway, much more than just the 1/8 inch gear difference would indicate. 8 3/4 is a fine rearend, ive got one in my eleven second mopar. But ive got a nine inch in my eight second car.
Automotive dictionary... thanks Tony. I need to remember this video.
Nice info Tony! Simple and informative. I remember a lot of guys talking about the ford 9inch but had no idea it was harder to turn and that the pinion was set lower for strength. Good stuff!
The Fomoco 8.8. So glad you gave this props. And even a shoutout to the Explorer. Im ashamed to admit, but the Exploder is actually my favorite truck. So versatile, not to mention parts for them grow on trees.
Great heads (GT40/GT40P), very strong little roller 302, and an awesome rear axle. Those things are a picker’s dream.
Uncle Tony you need to write a book on HOW TO Hot Rod for Dummies . Cheers
It’s me, you invited the comments so: nothing says I’m stronger than death than constantly having a smoke in your hand. I love the content and the invite to smartassery , woopwoop
On lowrider impalas of 1958 to 65 they use Toyota truck rear end it's tiny and clears the rear fender skirts when it pancakes to floor.
I got a 8 inch Ford rear end in my cougar right now and while it did explode on me. It has treated me fair on gas mileage and reliability. Just gotta make sure it has oil in it is all. Damn wheel seal went out and I didn't notice till 50 miles from home.
I met a guy at an NHRA national event running an 86 Malibu with a big block Chevy.
He was running low tens and lifting the front wheels in first and second. Beautiful car.
I looked under the back of the car and he was running a 7-1/2" ten bolt. I asked him about and he just held up both hands with his fingers crossed and said "I'm on my second season. No problems yet'
Never would have believed it if I hadn't seen it myself.
The 8 3/4 rear end is a great differential. The one thing you'll want to do to make your life easier is to use Green bearings retrofit axle bearing. The original bearing have to have the tension on the bearing set, but not so with the green bearing. This lets you swap center sections easily, so you can run3.55's or higher gears in the street and swap in a set of 4.30's with positraction on the weekends. My friend would haul a small trailer with him to the track which held his slicks, front runners and strip gears to the track. Whenhe got there it was a fairly simple swap to make, except catching the gear oil and pumping it back into the differential once the center section went back in. The only problem with this trackside surgery is dust, and gears and bearing don't do well with dirt in the oil, just like your engine. So, if your track has a paved pit area this might work for you. If not, you may want to go dressed for battle!
Thanks for the great new info - always learning. Didn't know that about the 9" Ford rear Vs the 8 3/4. I didn't realise the 7 1/4 was that good. I had a 71 Challenger 318 H price code Slapstick auto with one of these in it and was surprised to see that - unless someone swapped it out at some stage - will never know. But it had several chunks of metal from the crown wheel floating around in it and it was only a totally stock smog 318. Next video coming up is the one on pinion snubbers!
Excellent info uncle Tony
Cheers👍🏻
Franc
i can remember well, back in the day. you,d see just as many 8-3/4s at the digs as 9 inch fords. i saw alot of oldsmobile pumpkins too. kool that you always consider parasitic horsepower dragdowns because its huge. big daddys got smokey yunicks old custom made device through gm. an electric power-source that spins a non-fired motor. measures down to how many horses internal friction[s] consume, then each supplemental and sequential you bolt up afterward, tells you crazy things like how many horses the oil pump requires, or the drag of different timing chains...no wonder smokey was known to "wring out" every last available horse out of his engines, garlits says hed work weeks for even 1 more horsepower...far out....a lincoln versailes is a great swap for street or mild to light race duty, if you can find 1...mildly narrow width...9 inch...traction-lok diff....disc brake setup....a 10-bolt chev is a little stronger than people think, if you eliminate the c-clips, and i think the poncho is the strongest 10 of the generals and can work ok for street/street tires...i also remember seeing many, many 6-cylinder firebirds during servicing that had 10-bolt posis in em factory, why... i do not know.
Okay...
I listened to and (89%) understand your explanation, it makes sense. I see *way* too many people go for Ford 9s or D60s because "They're the best, bigger's better!"
Though they're under powered & can't get them to work to their potential, all of them subsequently complaining about "traction issues" or dogging or "weirdness" off the line, etc. and immediately leap down rabbit hole after rabbit hole. 🕳 😊
That said...
Here's the back story of my ride so you (and/or another viewer) may possibly, properly (hopefully) answer my question(s) and keep me from going off track (see what I did there? 😊). This is a bit of a different, progressive build so, I'm a "more info is way better than no info" kinda guy when seeking help. 😉
I'm in a stock bodied, '74 Road Runner, running a 440 magnum with a cam, about to get the heads reworked for "happy flow" (nothing stupid, massage the valve bowls for equity of volume, open/polish the runners, compound valve seat cuts, etc.. For now.
I'm also undoing *a lot* of mistakes that someone before me inflicted upon this thing. The trans is being properly built and re-valved for what I need and, I'm losing the carbonator (someone put a Holley double pumper on a single-plane manifold, leaving a nice hole in the power curve) and adding a full, Pro Flow 4, SMPFI system with a fuel sump to eliminate starvation, start *when I want* and achieve the best possible fuel usage. This also lends itself to (one day) putting a nice, Paxton "hat" on top of its handsome, little head. 😊
So, the power is coming, eventually. But I'm still not going for a 1,000+ HP monster, just a healthy 5-600 or so, allowing that 4k lb. sled to get out of its own way and, maybe even surprise a few people... And this is where the questions start, trying to get the most effective suspension/rear end setup to effectively take advantage of the power on hand.
In the meantime, it's just a naturally aspirated, unbored, unstroked, 440 magnum plant so, it's not generating crazy amounts of power.
It's got a 3.91 gear that someone put in the rear, not understanding that it won't work with the (now cooked and currently being rebuilt) 3spd. transmission. I actually want to keep the lower rear gear for those "special occasions" so, I've ordered a Gear Vendors double overdrive unit for it. This will give me a 3.03 final drive for cruising the highway and not chewing through every gallon of gas within a hundred mile radius. (Pretty slick, eh?)
The gears sit in an 8 3/4" rear.
It's time to replace the worn, factory springs and add some urethane bushings to keep everything happy but, I'm not sure if I'm better off staying with the current style, leaf spring set or going mono-leaf and, if running a Cal Trax set-up is worth the $$/effort or, do something altogether different.
I'm building a street/strip cruiser that's definitely more street than strip but, whether I'm "street fighting" or going out for a true, "strip adventure," I'd like to find the combo/compromise that will give me the best balance overall. Although I understand the basics, I'm not personally experienced with mono-leaf springs and the Cal Trax system so, given what I'm driving, which way would you go and what tips for "tweaking" it do you suggest?? Thanks for taking the time. 😊
This is the movie i was needing love my 8 3/4 in my 56 f100 that sure grip hooks up
Thank you for this uncle tony. I have a 8 1/4 in my mopar and have been thinking about swapping it for a Dana for a while but don’t wanna fork over that money. I’ll just keep my 8 1/4
Love your knowledge.. thanks for keeping it real.. GOD BLESS YOU..👍👍🙂
The 7 1/4 is great if you don't pile a bunch of power on it. I still can't believe how long mine held up. Tony sure knows his stuff...the spider gears are often cringe-worthy when you pull the cover. I like how this channel covers what most others don't know and pass off as irrelevant.
I like dropout third members and have an 8 and 3/4 in my hotrod...It had a broken cap and I had billet steel caps installed by Mark Williams...Also a crush sleeve eliminator too...Ford had straddle mounted pinions back to 1933...In fact I think the 9 inch Ford uses the same bearing...
The pinion being on the bottom of the case and ring gear also causes them to break off at the pinion (spit the pinion) and destroy the underside of the car when the driveshaft throws it around lol. The 8 3/4 is (in my opinion) superior to the 9 inch
Got a 96 Cherokee with an Chrysler 8.25 and it's lovely.
In my area mopar axles are 2 to 3 times as much as a 9", and 9" are getting expensive. Putting one in an early 55 Chevy pick up as we speak
Yukon dura grip carrier and gears is what i run in my jeep and k10 hooks up very well
How can anyone dislike this video? All you did was give good info.
This guy knows his shit. Enough said.
Miss early production videos on UTG !!
Dana 60 in my van. Very happy.
Maybe I’m a nerd, but I can’t bring myself to run anything smaller than a 1.5 x 35 spline axle. I only play with big blocks & I’m done breaking stuff.
I’ve noticed that the 14 bolt GM axle & the Ford 9 inch both use a 3rd pinion bearing & I think that has more to do with a pinion housing that is not cast into the differential carrier. With that said, I’ve never had an 8 3/4 fail
Danas are way heavier than 9 inchers though.. it's just a better choice, because theyve been the go-to diff for so long, theres so much support and you can buy aftermarket everything for them. gauranteed if you break down in a small town usa, you can find the bits to getyou going at the local autozon e. Hey you can beef that 8.75 housing up by welding gussets of 3mm steel from the top of the pumpkin folded to same width and out about 4 inches tapering back into the axle tubes.. julst copy the pictures on the strange engineering website ;)
TONY, THE NINE INCH IS LEGENDARY. IT IS THE STRONGEST AND LIGHTEST. A 9" HAS THE PINION SUPPORTED ON THE END UNLIKE THE DANA WHICH DOESN'T. BUT IT'S TRUE STRENGTH COMES FROM THE RING AND PINION CONTACT POINTS ARE ON 3 TEETH AS OPPOSED TO THE DANA THAT CONTACTS ON 2 TEETH. THE 3 TEETH CONTACT POINTS IS A LITTLE KNOWN FACT OF WHERE THE FORD TREMENDOUS ABILITY TO HOLD POWER COMES FROM.
“Drop-out center”. We call those “pumpkins”
Nice info thanks unk 👍👍
Tony, I have to disagree with you about the 7 1/4. After I replaced the 170 Slant Six in my '63 Valiant with a 180 HP 273/4 speed, it didn't take very many speed shifts and power shifts to destroy those spider gears. I went through a couple of rear ends before I grew up and started going easier on the shifts. Dumb me, I should have gone with the rear from that Barracuda that donated the engine and trans!
I use the 7 and a quarter in my circle track car with welding spider gears never had any trouble with the rear end but snap the driver side axle
Awesome Uncle Tony《☆》My 73 Dart Sport 360 auto has a 7-1/4 suregrip. It was fine till I put a bigger carb & 15" cop car wheels on it. A few hard launches & it spit a bolt thru the rear cover. Luckily Mopar performance sells a ring gear bolt kit for them. Not sure how well it works yet but I'm going to give the 7-1/4 another shot when I finish up a zillion other items on the old rust bucket🤠☻🤠
..That car/combination may be a bit much for even the stoutest 7.25
@@UncleTonysGarage 《☆》Thanks :*: I will definitely forewarn the future owner. I'm also concerned with rust issues like the rain rails & subframe so it may just wind up being a running parts bin 😖☻🤠
I’ve got a 9” in rear and Dana 44 in front. Driveline losses are real, but even with 35” tires on 3.50 gears, with manual trans, not worried
The new 8.8" f150 and 9.75" f150 diff 2015 and up are strong as hell also and also have factory disc brakes. The junkyards will be full of them and the 9.75" is VERY similar to a D60
I love how Uncle Tony always has a cigarette in his hand ,that's old-school baby!!!
I rebuilt my 8.25 Chrysler diff. It wasn't that difficult to do. First I started trying to tighten up the backlash to get rid of the clunk it had because of all the mileage, but that caused a vibration. I could not get it within specs. 4- 10 thou or something like that. It wore a bit egg shaped or whatever. So I drove it for a few months to work and back, all city driving, and it began to smooth out, and I thought it would work, but then I had to take a 3000 mile round trip on the highway and it did not get better. The vibration got worse, so I ordered the new parts for a rebuild, and right after the rebuild, on the test drive, though the vibration was better, it was really still there. So what happened was that what started out to be vibration from the out of spec diff that I tightened up, though it began to improve in smoothness, the other parts were taking a beating and began to cause their own vibration, and I was fooled by this.
So I ended up replacing both u-joints, a transmission tail shaft bushing, motor mounts and transmission mount, in addition to the diff rebuild, but wow! Smooth as heck now, and almost 2 mpg improvement, too. Like new, in the back anyway. So I know what having a 1/2 new van feels like, anyway. 530,000 or so miles on it now, but man is it smooth going down the road. A pleasure to drive, yet.
Yeah its like the 7.5 ford diffs. some say they are weak as hell but really they are pretty good. Again the spider gears are the weak link. Put a Auburn lsd diff in there and a stud girdle good for 450hp.
those 8.8 fit nicely in my S10 V8 u get posi trac disc brakes and very little customizing just a hole or 2 to expand, brake hose adapter and change bolt pattern or just run ford wheels
The pinon nut came loose on my 67 one day driving it,,,,4 spider gear sure grip,,,4,10 ..the nut was captured in the u joint,,,i had to keep it loaded up so the pinon gear would not slip back and make bad noises....just had to replace the pinion seal,,witch is made of leather,,,,,good times
Good stuff sir
I'm Building a street strip Squarebody (mainly street). I'm building off a GM 10 bolt 8.5. Gonna do a 4.11 8.6 ring gear with a 30 spline axles to give it a fighting chance. Probably going to get a Eaton Truetrac. Got a 700r4 Overdrive trans so I figure 4.11s will be alright going done the highway.
I like the AMC 20
Thanks for the lesson..... Really
Hey Uncle Tony, love your vids! I'm kinda new to Mopar, but I'm building a '66 barracuda with a 318 2bbl, A833 od tranny. All the old timers tell me the 7. 25" won't last. Any thoughts on how I can make it live longer? The engine is bone stock other than headers
That's a tough one. A Sure Grip unit will go a LONG way. Spiders are the weak link on those rears.
Im planning on putting a 9 inch in eventually, but I'll just keep an eye on the spider gears. Maybe even use some synthetic lube. Thanks for the input. Keep up the awesome work! You're the best!
Keep 13" wheels with 3"wide tires on it, till you get it swapped. Sticks and those rears aren't friendly.
Man what great info I didn't know.
Now that 8.75 third is bomb proof from that era. The
housing is easily trussed and tons of after market support. However, today their a hard find or folks want big dollars.
The 57to 64 Olds 9.3 is one of the stronger OEM rears but getting scarce and pricey to build. Very similar to the 8&3/4 and 9in Ford.Thinking of having one built for a 67 olds442 but it will cost some serious money.
For a car these may great, for me dealing in pickups and bigger even that 8.8 or 9inch is small and weak..
Just think a ford 9 inch in the back of my f600... :) snap..
3:00 UT's fatherly advice on picking a good rear end......😄
What's the opinion of the Chrysler 9.25? sorry if i missed this earlier in the comments. What kinda power can it handle, weak points like shock load ect.. @Uncle Tony, I'd love to keep learning about the 3rd gen Hemi and what a recommended budget upgrades for top and or bottom end. Especially for something like my 05 Ram.
Deciphering those tags on the pumpkins is like a second job.
Oh wait, the tag is missing...
I screwed up I had a 8 3/4 sure grip in my barracuda FS with 392s and I put a tall tire so it made it around a410 gear that car launched fucken awesome at the strip
What I hate is when you're working on something and you don't think the process through thoroughly. At this point you either break something or loose something and say why did I do that. Good example I was replacing the u joints on my 84 Corvette. I was greasing it up and the one cap popped off spilling the bearings all over the floor. I cleaned everything up and counted 27 bearings and the one that didn't fall off had 32 bearings. Where did the 5 bearings go I ask myself. Fortunately I work at an auto parts store so I get a discount on another one,but it still ticks me off. What I need is the comonsense angel tapping on my shoulder saying I wouldn't do it that way.
Tony the man
Always got a cigarette in the hand. Lol
I was gonna say that lmfao🤣🤣🤣🤣
yeah i think they're roll your owns
Did you ever notice all the guys at NASA always had a fag hanging out of their mouth, great stress reliever, get ready to launch a rocket ship to space or drag race a car down the strip figuring out the best rear end set-up, 🔥 fire up one of your favorite brands, go Uncle Tony🏎️🏁
I much prefer rear ends with the removable pig so all the lash can be set up on a workbench. Packard is the automaker responsible for the helical ring and pinion for quieter running with the pinion low to lessen the clearance needed for the driveshaft while Ford continued with beveled gears a few decades longer.
So true...the 7.25 is like the Slant Six and 318... Automatically discarded and/or underappreciated...
I had a 7.25 wirh 2.69gears in my 68 Dart. I was working on narrowing some 8.75 for it but never finished. In spite of what people said, that rear survived 2.5 years of daily driving and weekend strip action behind a 440/727 that pushed it to theb11.50s in spite of the ratio. It was still goin strong when i sold the car..
So i wouldnt be afraid to run one for a while til you can upgrade it guys...
Really? I have always heard if you spin them they will snap i have a suregrip or limited slip in it s6 to v8 swap 2.96 rear ratio 7.25 im deathy afraid ill snap it with the first year 318 high performance 4bbl one i have in it 1968 mopar 318 4bbl rated at 230hp and 340 lb of torque has high lift rv cam so probobly a lot more torque
@@timallred6789 Yeah...i mean, the consensus is that theyre weak. But maybe not quite as bad as everyone thinks. I was told itd explode first time I fired up the 440!! (It ran strong too with 10.2:1 comp, .484 MP cap, ported heads, M1 single plane, etc) but it lived for about 40k miles and right around 100 1/4 mile passes. Never broke or sprung a leak. I never even changed oil in it cuz I thought itd blow...but it never did!!!!
@@wheels-n-tires1846 must have been made on a Wednesday lol
wow living behind big block power I am amazed. In my limited experience, the 7 1/4 sure grip in my stock 318 2bbl 72 Duster grenaded after maybe 2 years of street driving, just my 'get me to school ride', took it down the strip a time or two but nothing too crazy. The spiders each had one or two teeth left on each gear.
@@bottomshot4546 yeah im sure im "one in a million" lucky LOL... I have no clue how it survived!!! But somehow it did, and I was never easy on it...
Good stuff. Dude, shit can those smokes. They are killers.
Wonder if they put those 7 1/4 in early 90s Jeep’s because grenaded two of those axles spider gears in high school.
The LSD differentials are much better for control , it’s amazing how it can snap you around a corner
"Somebody already found this one" 🤣
Yo Tony love you videos thank you for all the Information That you give us I need some help Please I have
1976Dodge Dart Swinger Slant 6 I am going to put a V8 in it Need help On What kind Of rear end Should I go with Don't have Lots of money So Looking Maybe Picking Up something At a junkyard or Secondhand Please Throw me bone Would be very happy😃If you can help Me out Thanks Tony You're the man
I have 2 7.5's and 2 7 5/8 rear ends I can blow until I put something better in it.
I got a 9" in my '56 Fairlane
Back again Tony!
My setup is a 70’ challenger 225.
Looking to drop a rebuilt purple cam 318 paired with a A833 OD… it currently has the 7-1/4 in it right now, would you upgrade to a 8-3/4 2:76?
My Plans for the car : Grocery getter, cruiser .
I’m about to throw an 8.8 under my first gen Charger. I’d keep the 8 3/4, but for less than a sure grip center section, I’ll get decent gears, an LSD, 31 spline axles and disc brakes by pulling an entire Explorer rear end. Same wheel stud pattern too. What’s not to like?
Plenty of 8-3/4’s have been under blown alcohol cars too . A little gusseting and it will last you a long time
Hey uncle Tony !! Im been binge watching your videos this evening . I just ran across this video and I thought Id ask you about something. I jave a '83 b250 van I been messing with for about a year. Ive been thinking about doing something with yhe transmission so I could end up with overdrive. My first thought was a gear venders unit. Of course those are a bit pricey. My next thought was to get a transmission out of a dakota with a 318 I haven't looked too deep into it yet but, I will soon. That era of mopar transmissions amd their reliability issues make me nervous though. Thinking about the trans leads me to the rear end. I have a 91/4 and I dont know much about it. What is your opinion on that rear end ? And, what is your suggestion for getting overdrive into my van? I use this van to travel with my wife and 2 kids so I want to do something thats bomb proof. My van has a 318 with what I believe to be a 904 transmission.
Honestly, overdrive automatics are something I have very limited experience with, so I can't really give you a quality answer to that.
As for the 9.25, they are extremely stout rears, but have been known to shred spider gears at random times.
I'm a big fan of a nice rear! Lol
No truer words have ever been spoken. One size rear certainly doesn't fit all.
I've got a Dana 60 in my. 70 Datsun pu flat bed being pulled down the road with a 230 H P 318 with a auto transmission