Another BAD Ford/Mazda 2.3L MZR Engine. A Propensity For Failure, Why?
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- Опубліковано 27 вер 2024
- For parts Email us at Importapartsales@gmail.com or visit www.Importapart.com!
Here's weekly dose of your catastrophic engine forensics! Every week you can find a new teardown of some abused, misused and/or poorly designed engine. Here are some of my favorites:
Toyota Prius CARNAGE • BLEW UP A PRIUS?! 2010...
Incomprehensible Honda J35 Failure • Obliterated Honda Acco...
6.7L Cummins Destruction • DEMOLISHED 6.7 Ram Cum...
The WORST Kia Engine Failure • Taking "Blown Up Engin...
Today's teardown is a 2.3L "Duratec:" or "MZR" Mazda/Ford engine that can be found in most of the mid-late 2000's Mazda and Ford Lineup. This includes the mazda 3, Mazda 5, Ford Escape, Mazda Tribute, Mercury Mariner, Ford Fusion, Mazda 6, Mercy Milan, Ford Focus, Mazda CX-7, etc.
There are many different variants of this engine, some turbocharged and direct injected, most of them naturally aspirated.
This particular engine is out of a 2005 Mazda Tribute that my brother bought to fix and sell. I sourced him a used engine to replace the bad one, and this core sat in his garage for a while. This engine has 158K Miles on it and its pretty clear what happened here. Many of these 2.3L's meet their demise in the same way and its still apparent there is demand for them because they are still relatively expensive engines.
Why am I doing this? My name is Eric and I own and run a full service auto salvage business called Importapart. Part of our model includes dismantling blown and bad engines to salvage the good parts to resell. We do not rebuild engines, merely supply parts to those who do.
I really hope you enjoyed this teardown, as always I love all of the comments, feedback and even the criticism. Catch you on the next one!
-Eric - Авто та транспорт
Yeah, I have quite the track record of not draining oil from engines and transmissions I remove from vehicles. Whether that oil ends up dripping down your leg from a RX-8 transmission or creating an EPA-alerting spill on my driveway out of my 3 rotor, I deserve that bus you threw me under. - the brother
I like your old Protege BPT Videos. Been thinking of turboing my DX Protege but the tranny won't like it
I still run my '03 P5 wagon, all stock with the sport stick no less. It still runs fine at nearly 200K on it. Yes, the FSDE 2.0L 4.
@@Shiznit304 Yeah the F-boxes don’t hold up well to boost compared to the G-box. My ‘94 is running stronger than ever, still on its original G-series, though I did destroy the diff once, about 10 years ago. Has a Mazdaspeed Protege LSD in it, all good.
Thank you for the engine! And uhh... Not ALL families do that.... Just saying. So thank you for your generosity.
You must be the black sheep of the family
10:15 - Cranks without a keyway are complete madness. It's negligible added cost and manufacturing time, while negating the need for a special tool to do a very basic service. Even if you aren't messing with the engine's timing, harmonic balancers do fail and need replacement on occasion. A keyway would make that job very easy.
Yeah, stupid.
Bean counters at work... Probably eliminates 1 step during assembly.
@@volvo09more engine failures, more engines sold - some CEO
Well they have to make compromises somewhere for your precious government.
Some know nothing bureaucrat.
The cams too.
But the oil pump!!! Yeah yeah yeah!!! we'll key that!
Madness.
I grew up in workshops. I ran a mechanical business for 12 years.
One day I'll be in a pub and get to meet some bloke who designs engines. I can't wait for that day to come.
Some people think time really runs backwards and the ancients were the tech people and we lost that tech. Heading for extinction due to our stupidity.
You're spoiling us with this two-videos-a-week schedule.
Agreed but I am happy with the results. : )
Keep the new tradition👍🍸
It's nice, as long as he doesn't get burned out doing it.
That engine was trying out for the band.
That drum solo...
Been following this channel since there were maybe 10 teardowns uploaded, and the fact that there’s a midweek video most weeks now is freakin awesome!
When I joined he had 67,000 subs. Now he's exploded to 308,000 and growing!
Between the Safety Tote, the cram craps, and the piston nuggets it's always a good time with Eric!
Don't forget to appreciate the bearing basket and the rod bearing concentrate....
A rack of Rod Bearing Concentrate bottles would be a talking point in the awaiting rooms at service centres everywhere....
"Now it's time to pull the bearing basket" Bearing basket!!! 🤣🤣🤣🤣
It’d* be a real pita to film but it would be cool to see two or more competitors’ engines torn down side by side, like a 3.6 pentastar vs a 3.6 gm, and compare things 1 to 1.
yes please. and so many 2.5L!
As well as 2gr and vq35 and j35
I was waiting for the "Uncle Rodney" reference as soon as I clicked, but the subtle Rodney Dangerfield reference was perfect.
Ive seen alot of these 2.3's blown up so i cant deny their tendancys but I have a daily driver cx7 with the turbo 2.3. It has 200,000 miles and is still running strong. I drive it an hour everyday on the highway to work, but I also check the oil every 3 is days and change it every 5k miles. Fingers crossed it's lasts many miles yet. Awesome teardown video as always man!
WHERE WAS THE TEST? WHERE WAS SCIENCE?
Eric, you forgot!
It was a running engine.
I've got 406,000 miles on my Duratec 25 in my 2012 Ford Escape - besides a few plastic parts breaking due to wear and tear such as the water coolant outlet, the ac condenser springing a leak, and a few fender benders - she's still a great daily.
Here's a big thing about the 2.3 / 2.5L engines; The same bolt size that you use to remove the coil pack when you change your spark plugs, is exactly the same size as the valve cover bolts, not only that, they are literally less than an inch apart from each other. If a clueless person were loosen just one bolt on the valve cover and fails to retighten the bolt to spec with a torque wrench,, it will eventually cause oil to bypass the gasket at some point, and cause oil to be forced into the spark plug area, and thereby into the valve bleeder valve and back into the intake through the throttle body.
This will cause insane idle problems (a gunked up throttle body can turn the escape into a demon), spontaneous shut downs, and total loss of control at the worst possible time.
The simple remedy is to check all your head bolts and valve cover bolts with a torque wrench set to factory specs every time you change your spark plugs.
If you've had a perpetual oil leak, this is potentially where it is found. If it is a severe enough leak, you will see oil pooling on top of the actual spark plugs. not good.
If only the Duratec engineers considered changing the bolt pattern between the valve cover, and the coil packs... then again - cheap is big business.
I just looked back, and it appears I have been viewing since summer 2020 and have loved every moment. Eric, please go to Harbor Freight and by a cheap small band saw for cutting stuff up. I am a cabinetmaker and have cutoff tips off 2 fingers, and I don't want to see you get hurt. Chop saws are not your friend.
I've got a 2.3L 09 Ranger. My biggest gripe with these in the trucks is they only hold 4 quarts of oil. Mines doesn't burn too much, maybe a quart over 1500-2000 miles. But that's still a lot of the capacity. Oil temp is probably on the moon too, even full. I like the simple little turd, but I did also use to own a built MZR in a speed6. As you said, I might be a bit of a glutton.
My 09 doesn't burn any oil
You forgot Safety Tote with the chop saw, we almost lost you!
I remember the 1970's Ford Pinto engine used in a lot of European Fords and some American. It had a spray bar running over the top of the single cam that sprayed lubricant onto the lobes and when owners failed to service and change the oil regularly the spray bar would block up, fail to lubricate and drastically wear out the cam.
Can’t fix lazy owners
The pinto was almost unbreakable even for taxi drivers and builders😂
Had one in an 07 Focus ZX4 ST. Original owner. 219k, started every time, never consumed or leaked one drop of oil. Bottom of that car was bone dry the day I sold it. Ran exactly the same for all 219k miles. Good low end torque for a 4 cyl, way different approach than anything Toyota or Honda were making at the time. Was nice to have power down at 3k RPM, and not have to be up against the red line into the VVT to get power out of it. Needed an alternator for $400 at 120k miles. Only unscheduled maintenance I ever did on it. Guess I got a good one. Was a good car. 219k on the original clutch, brakes (yes, brakes), everything. Only thing I ever replaced were tires, wiper blades, and that alternator. Averaged 31 mpg for its life. In some ways I wish I still had it.
Agreed. I have one in a '07 Mazda 3. Never replaced anything but consumables. Runs as good as the day i bought it new. Never burned a drop of oil.
Lots of torque for a 2.3
This video hits close to home. Owner of a 2007 Mazda 3 here. Original owner at 107k.
I love these, and the 2.0 even more. I changed my oil religiously though so that's prob a contributing factor. My profile pictured 05 focus 2.0 had 470k before I sold it to a friend.
my father has a 2007 mondeo with a 2.0l engine and it's well over 300k km. all you need is regular oil changes
Same here, I'm actually surprised with his opinion of these engines. I've had 3 of these in my family, all had over 200,000 miles when sold and ran great! One of them actually DID nearly run out of oil a few times (pcv valve failure and bad maintenance)...it kept going though
I had my 08 Focus with the 2.0 liter go to 230k before I sold it. Still ran great and never had any major issues. Just a spark plug well seal leak. Changed oil every 7500 miles
@@conmanl4959 yeah the valve cover gaskets turning into plastic was very common. I never had to make any major repairs either other than an alternator and a starter.
@@conmanl4959 I sold it to my friend and he didn't even make it to 500K before he totally trashed it and it went to the junkyard. I was actually kind of upset that I didn't get to see that car make it to 500k.
Fantastic Lighting for the "Bearing Sauce" and the Wear/Damage of the Oil Pump, also very much appreciate the close-ups of the damage.
Great Content, Thank You.
Back in their day, the L3 was a glorious compromise between the lack of power on the LF and the NVH on the L5, all while getting the same or better economy as the LF.
When you said speed 3 owners are gluttons for punishment... sir, I did not come here to be called out.
But you're right. And yes, I carry a gallon jug of top up full synthetic with me everywhere. My 09 has 326000 km and as tired as it probably is, it's still going. I check the fluids every time I climb into it, and its treated me well for the time I've had it. For a C$2500 budget racecar with a long history, i know its going to give up eventually. I'm just gonna enjoy it while it lives
Noo ! Engine knock ? Throw in some a synth , glow sticks , strobe lighting , and you've got a rave.
Can't stress how important maintenance is for one of these MZR engines. I have a dead stock Gen 1 mazdaspeed3 with 181k miles on it. I bought from the 1st owner who maintained it meticulously and have put about 40k miles on it so far. The car's been serviced religiously with oil changes every 5k miles. Other MS3 owners tell me that 181k is "above average" for the original engine, but I'm also convinced a lot of MS3 owners mod their cars and don't change their oil regularly
I own since new a 2009 Mazda 3 with this engine and it has 223,000 miles on it.
I had a couple of emission related issues and that's about it for the engine.
It doesn't burn a drop of oil between 5000 mile synthetic oil changes.
This is by far the best engine I've ever owned.
I have virtually the exact thing going on. 260000 miles,,never burns oil, drive it every day
So where was your engine built????
Window sticker says Japan@@JohnSmith-yv6eq
That may explain it.
There appear to be significant quality differences between Japanese/ European cars manufactured in USA/Mexico
and those made in their "homelands".
@@rhino6285
mine burning lot of oil but it was neglicted by previous owner, good engine though. I am going to rebuild it myself.
This channel is something sane in an insane world. Thanks broski!👍
Any engine you tear down, I love watching.
Knocking on the 250K door with my Mazda 5 (2.3)! So far so good!
Don't forget to check your oil level frequently and you'll be fine!
Looking for a manual mazda5 now...many clean 2.3 versions out there but this video scares me. 2012 and later manuals seem harder to find!
I hear that drummer on a street corner. The guy was playing some 5 gallon buckets, and probably made more than all of us tax free. Motor sounds great!
An excellent educational video on the perils of not maintaining an automobile. Kudos to you and your brother for donating time, effort and expertise in making this information public. Cheers!
Thanks for the mid week teardown. That was nice of your brother to provide an engine 👍.
Thanks for another mid-week video! They're great and make the wait till Saturday much easier! 😁
Well. It’s certainly NOT the 2.3l engine I had in my ‘85 Ranger.
Was like a little tractor, just keep it maintained and it just won’t die. 😂
I drive a 2006 ford escape with a 2.3 and it has been in the family since it was at 26k miles it has about 315k and it has been a great engine. Replaced the spark plugs one time, and a valve cover gasket. Other than that. She has ran strong. I’m religious on my oil so that’s probably why
Hi. I’m in A town near Glasgow Scotland. I watch all of your videos with interest. It’s great to have content that doesn’t have the usual over produced crap in it. I think the tear downs are great I I like the stuff where you get a piece of crap running again, like the Miata (Mazda MX5 to us Brits)!!!. I find that I learn much more from those videos. All of your content is great. I love it all and see you on the next one. Thanks
did you watch the Bentley teardown?
this engine played drums for my band in 2003
wha-wha-wha-WHAT?! NO SCIENTIFIC TEST??
Alma Boykin's "Familiar" series has a character who becomes known as "Uncle Rodney". He's a talking fox who assists with magic. He can't handle his mage's spicey food. His mage gets sick thinking about what sort of wild catches and finds that Rodney eats.
My 2015 2.5 Skyactive GDI is clean and running great due to 3k OIC's since purchased. Now 89k miles.
You can run 5k mile interval safely on that engine. I think 8k is also safe with good oil and even a little more if you have a lot of highway miles and you're doing more than 2 changes a year. I'm at 203K miles on my 2L skyactiv GDI and you really have to try to screw them up.
I still daily drive a 2008 MazdaSpeed 3. STOCK! Started burning oil around 90k, was consuming it at an alarming rate(like 1qt every fuel tank) when LSPI finally killed it at 157k. The engine never lost rod bearings, ring lands got crushed and cyl2 went to 10psi.The car got oil changes ever 3000-3200miles(at most). Have a new Gen2 based longblock in the car now, 16k miles and SO FAR it hasnt consumed any oil
We didn’t complete the scientific variable compression test? What is this world coming too!?!
One thing is for sure, the numerous plastic parts used in modern engines are never points of failure.
That thing runs like it's about to feel the air of night
That engine drum beat made me think Mr. Eric was gonna rickroll us.
I have a 2011 Mazda 3 i with the 2.0 currently. I probably overpayed for it but desperately needed the car at the time. When I was told "the second gen are the worst of them", I was rather disheartened. But even knowing it largely comes down to how it was maintained, hearing you say it's a good engine is a bit of a relief.
2007 Mazda 6 with this 2.3na is my work car. 190k and runs fantastic. But yes, I do the oil every 3k. I’m praying to see 250k before I shake it off. That’s if the glass trans plays nice😁
To be honest, it looks like a simple and well engineered 4 cylinder. No VVT or GDI to muck it up.
I had a 2006 ford fusion with this engine. Had 250k on it when we sold it. Never had a timing chain done and the water pump only started leaking at 240k. Had nothing but good luck with it. Never burned oil
Engine sounds like Prog Rock or Jazz Drummer! 😁👍
Mike in San Diego. 🌞🎸🚀🖖
My dad owned an 06 Mazda 3 with the 2.3. He drove it to 220k miles before we sold it to a classmate at my auto tech school. He fixed it up and as far as I know, it’s still running.
When we sold it, the engine was burning about one quart every four days, or every time the gas tank needed to be filled. 😂
Yeah, in the speed3/speed6 community it's very common for a balance shaft delete. More oil! We need it when our turbos burn all the oil and destroy themselves!
Gerotor oil pump. Thanks to your brother and I enjoyed this video. My son's early RX-8 (which he tracks and autocrosses) original rotary is till running well with over 100K miles on it so far - those daily Italian tune-ups probably help. I wonder how long my 2020 WRX will last considering I got over 216,000 miles on my '98 Neon Expresso - which I also autocrossed and ran road courses (plus one drag strip day) on the same engine with zero repairs. Guess we've been the Wednesday build owners! 😀
*"Except Subaru!"*
I just got done putting new rings in my '03 Forester. Got tired of 1000 or less on a qt of oil!
The oil rings were glued to the piston. The little oil holes behind the oil rings were filled with carbon that was brown! I literally had to use a drill and a small bit to open them up! I have around 400 miles on it since the engine work. Don't know if I was successful putting it in a 12 step program or will it relapse? LoL 😂😆
Authentic mid week stuff 👍
I love my 03 focus 2.3 but I'm meticulous on maintenance. I honestly wish I still had my zetec 2.0 though It seemed to be better balanced. The duratec vibrates a bit more than I like.
The camshafts not having a keyway is the primary reason I will never do any work on the family 2009 Mazda 3 Neo BL. I'll do oil, plugs and filters - but nothing else.
As for run videos of failed engines. Watching one of the 105 series Landcrusier 1FZ-FE my friend bought with broken ringlands for $500 (pistons 1&6 - was turbo'd), ran and sounded like normal turbo 4 cylinder - but still with similar power to what it would have been stock.
What do you mean "It didn't sound good"? It sounded downright catchy! Sort of like drumsticks on the rim.
You know Eric i really appreciate the hard work you do to have 2 engine tear downs per week. I hope your wife and baby are all well. I love your channel and your humour.
Thank you for a Thursday morning video (New Zealand time frame)....
You are a great person... Please keep it up....
Man that engine run video had a rad back beat to it! It would take 3 spoons just to make that again....
Bearing basket, bearing concentrate…love it! 😂😂😂
Like to see you tear down a 2.0 GM diesel that were installed in Chevy Cruze
I love these engine teardowns because they give me background noise whether that’s for doing chores or sleeping. It’s been super awesome helping with that
Knockeroni and cheese? Great one Eric.
Love the "engine autopsies". Would love to see an A25A-FKS teardown eventually.
I love my 2.0 08 Mazda 3! Great little motor. 130k. Never burns oils and I swear at 5k the oil always looks super clean.
I have a rare 2008 Ford Escape XLS manual trans with 2.3L engine. Mine is only at 133k miles, so not so much. I just bought it recently. The engine is in phenomenal shape for its age and runs perfectly once I got the throttle body cleaned out a bit and swapped the EGR valve to get rid of the money light. I've had it long enough to change the oil and mine was down maybe a third of a quart after 5k miles. I do use oil additive to help with the efficacy. Maybe I'm one of the lucky ones, but I've had it checked thoroughly by a trusted mechanic and we can't find anything wrong so far. Runs smooth and has plenty of power. It's cool to see a teardown of this engine. Thanks for the vid!
my friend bought an 05 xls manual 4wd with 176k and little apparent previous maintenance. It now has 205k. he's pretty hard on it too, but he keeps oil in it, and that's enough to keep it running great. does yours have cruise control? his does not. Enjoy, they're pretty good cars for what they are
Special thanks I DO CARS I picked up the timing chain from this motor today . I was in Missouri on spring break from Cedar rapids I clearly enjoyed going to importaprt. I can't wait to come back for more broken parts
That's the sort of damage you'd expect from any engine that was poorly maintained. What I've learned about this motor is that the 2.3 variant really doesn't like high revs as its crank is weak and often just snaps totalling the engine. Now that's a true design flaw.
Drove a 2006 Mazda 3 five speed with this engine for eleven years and finally retired the car at 265,00 miles!!! The Body rotted out but engine still ran good. Car was great and had a great engine.
I loved my 2.3 in my ford fusion. Was slow. But got good milage. Only burned like half a quart in 3500 miles oil change intervals. Ran great. Just really noisy on cold start-up. Escpecially in winter
Did you run too thick an oil so that cam chain tensioner couldn't move quickly to take up the slack and stop chain slap?
In the uk we had a lower cc engines in the mondeo/fusion and focus and various mazdas the worst one was the 1.8 duratec-he and from new they burnt oil or swallowed swirl flaps if they were hungry. It was down to gummed up oil rings, hardened stem seals or busted egr valve. Always happened even if you changed the oil every Wednesday.
I'm only here to see you toss the water pump ...LOL
I remember those early 2.3's also had an issue with the oil pick up being too close to the bottom of the oil pan and starving them of oil. I believe Mazda had a TSB but not a full recall for them where they fixed it by either changing the pick up tube or the oil pan, i cant remember.
That run video sounds like it's making popcorn
thank you Brother Eric
I use Mazda Tribute 2005 with 2.3L MZR Engine. Since 2005 to now(2024) milage 312,000 Km still running in good condition
In OZ we got them in the Mazda 3 "SP23"...Mostly manual gearbox and very prone to kicking a leg out....Mostly due to poor maintenance...Delamination of the Alloy bearings...Notice there is no "Locating Tang" on the main and rod bearings...I've rolled a set of bigends in one and saved it from a messy end...
The 2.3 in the mazdaspeeds and mps really need to be looked after well. This means regular oil changes (5000km) , injector services, egr delete, valve cleaning and some other stuff. It’s quite expensive to own them, but they’re a lot of fun. I’m running 380hp on my 2.3 mzr and it holds up pretty good. In the lower rpm you’ll need to baby them a bit cause the rods don’t like torque that low in rpm. Also the hpfp needs to be swapped with a better one, the stock one makes the car run lean in 4th,5th and 6th gear which will cause burned piston and eventually a rod through the block
I have a 2.3L Fusion, it works great! 260K miles on it, burns zero oil. I beat on it all the time, took it to track days, etc. Gotta keep up on oil changes, but that's about it.
That run video…
Sound like cool, eccentric, beat for an artsy song
I'll say that i have a customer with an '08 Mazda 3 with this engine. It has 277km on it and pulls to redline without any problems. At 6km oil change, average level is down between 1/4 and 1/3 of a litre. Ill assume this engine is the exception that proves the rule. Great to see you midweek. Cheers
I will say though that the 2.0l and 2.3l both have the PCV valve behind the manifold which is a pain to change, and responsible for a number of the engines that die from low oil level.
I love mid-week pick-me-ups.
Ive got both this engine and the updated duratec 25 in my fusions. the latter one is about to hit 300k after a long life of abuse. The only problems they've given me is a leaking water pump at 160k, and valve cover gaskets. the 23 is only at 115k though, and it is absolutely gutless compared to the 25. I always thought they were pretty reliable little engines though. they've served me pretty well. Now I'm gonna be checking the oil religiously on the 23. That timing system looks pretty simple to work on despite not being keyed too; a helluva lot better than their new wet belts anyway.
2 friends had 2.3 escapes. 1 had over 200k. Both did burn a lot of oil!
My wife had a 2007 Mazda3 with the 2.3 MZR. The engine never had trouble or even burnt oil, but it went through three transmissions under warranty before we got rid of it when the warranty was up at 100k miles.
I'd say that EVERY engine without oil has a propensity to fail. In fact I might be so bold as to guarantee it. Oil is cheap...
Got this engine in my 2007 Mazda 6 GY. 290k km (180k miles), runs as good as the day I've bought it @180k km (113k miles) little over 2 years ago. Preventive maintenance is the key. Oil change every 5k km (10k max) / (3 - 6k miles), check belts / rollers and so on. Only things I had to replace was AC compressor 1 year ago and starter motor last month.
That knock was spitting a decent beat.
I have a 2008 Ford Ranger with a 2.3 L engine which I believe is a Mazda L engine. It has 380,000 km and is still in good shape, not burning any oil.
I'd like to see a blown Ford/Mazda 2.5L non-turbo but I'm not sure they actually fail. Mine has 211k on the clock and has had exactly zero problems
Mine too, doesn't burn a drop.
I own a 2010 Mazda 5 with the 2.3l. 145000 miles purr like a kitten. Change the oil every 3000 miles no oil consumption maintenance is everything good work again!!!
I know ppl with Subarus that have 300,000+KM on them. Maintenance is the key, Oil changes, good oil, and don't do every 10,000 or 15,000km. I have a 2018 Subaru WRX and I do oil changes every 6-7000km.
I gotta say I had a 2004 mazda 3s manual for 8 years. I loved that car. It only needed oil changes and brakes for 209k.
What did my 2007 Ford Ranger had? It had a 16 valve 4 cylinder engine. It had 270, 000 miles on it when I sold it last summer. Changed the oil every 4K miles. Never had any major issues.
Thank you Eric!👍
That engine made me long for my trip to the Caribbean. It sounded just like a steel drum band I heard in St Kitts.
I've been a Ford dealer tech for almost 30 years. I own three Focuses(2005ST, 2006 and a 2013). The 2.3 in my ST is bulletproof, as well as the 2.0s in the other models. I have seen the 2.5L variant in the Escape models crack blocks between number 2 and 3 cylinders, but I've never seen an Escape or Mariner 2.3 fail...
@@devenmellor Yeah, the dual clutch transmissions are an issue, but I can knock a DPS6 clutch out in around 4 hours, as I've done so many. The Duratec 3.0 is pretty much bulletproof too, but when they get up there in mileage, the timing chains and guides wear out and would need to be changed. They also tend to leak oil from the timing cover over time. Otherwise, they are reliable as hell. The early 6F35(it was called a 6F Mid by Ford at the time) were much better then the later models actually called a 6F35. I have rebuilt dozens of 6F35s over the years and have a good track record with them. You can flush the newer ones as much as you want, but once the torque converter has had enough, the trans need major work. It's cheaper for most people to just replace them, but under warranty we had to fix them. The 6F35 has been out of production for a few years now, so most of them are out of warranty and I haven't done one in a while.
You forgot to do the "Test" with the Hammer! LOL
I finished up with my Dads 41 Pontiac about 1963 it had been an Army vehicle (No Nickel) although Right hand drive, so Australian assembled. Then because it had a Commercial Vehicle plate attached we assumed it was used as a Taxi in Toowoomba, I think I watched it turn over to all zero's ie 100,000 miles most likely for the third time. My Dad had put a new timing chain in it but I found the timing chain very worn, not too many thousand miles later, but there were no guides. I should have made guides out of Iron Bark timber, (Google Australian hardwood) that would have lasted the rest of its life. Ted from down under.