4L80E Basic Rebuild - Part 2

I continue the build, picking up with the intermediate clutch then assemble the forward, cost clutch and overdrive clutch drums. From there, I tackle the pump, assembling it in stages and test the stator support on the Sonnax vacuum test machine to validate all the valve trains are adequately sealing.
Lastly, I install everything into the case for the final time, closing Part 2 out with a front end play check and adjustment.
Note - I break up the pump assembly process to accommodate the testing but decided to film the assembly of the overdrive clutch piston/housing assembly prior to pump assembly to tidy up the bench...You can assemble all the non-rear gear train sub-assemblies in any order that you'd prefer. This is just the order I did things with this particular transmission.
Table of Contents:
Intermediate Clutch Set-up: 0:00
Direct Drum and Int Band Install: 27:18
Forward, Coast Clutch, Input Shaft: 34:51
Pump Assy and Vacuum Testing: 1:05:11
Overdrive Clutch Housing: 1:46:30
Input Shaft-OD Planet Measure: 2:02:00
Pump Final Assy: 2:04:07
Forward and Coast Clutch Clearance: 2:08:26
Front Case Assembly and End Play: 2:19:30
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[@Roscotech]

I may have mentioned this before but in a pinch the green “Lip Wizard” disk that comes in many of the Transtec kits makes an excellent sealing ring stretching tool! Roll it up tightly into a cone, put the new seal onto the small end of the cone, make the big end of the cone fit the shaft you are installing the ring onto, then push the seal down to its groove. Works great without stretching the seal too much. All bets are off with resizing. Sometimes you can use the drum you are sealing if there is a generous chamfer but the proper sizing tool is best! Those rings need to be perfect! The worm clamp method usually leaves an indentation on the seals…….BAD! I have seen guys use PVC pipe maybe a little oversized and cut it open lengthways. Adjust the gap so that with a worm clamp around the outside of the pipe you can tighten it down into a no-gap situation and resize the seal with no marring. I had also done that same thing with bushings, preferably a bushing that is used in conjunction with those particular sealing rings (like the C,D,F drum on a 10R80). Basically anything that doesn’t leave an indentation directly on the sealing ring.

[@nickstransmissions]

Thanks for watching and commenting Ross and great tips for alternatives to sizing tools!
The hose clamp method is ok to use with the caveat it's done correctly, I know because I've done it countless times prior to obtaining all the resizers I have for each transmission...But the caveat is the hurdle for many including me as it's all too easy to get too aggressive, too tight and damage the sealing ring...
Anymore, I just buy the special tools but the Transtec green disc-shaped lip seal tools is a good technique and doesn't seem to carry any downside risk.

[@johnsimmons8456]

Holy hell, a video where someone is actually checking vac on the pump, as they should.

[@nickstransmissions]

Hi John, thank you for watching. Yep, don't see folks do this all that often on YT though most builders (at least the competent ones) have this equipment and use it religiously...

[@hybridmusclegarage4590]

Awesome man!!!! You always have the best video's

[@nickstransmissions]

Thanks a ton, HMG!!!

[@Roscotech]

Also I am building one very similar to what you are doing here. Stock application, 3500 series truck (93) with a mostly stock big block. My forward and direct clutch clearance are near identical at 0.069/0.071. I could tighten up either one with the spare steel plates I have but I’m thinking I will be good there. Haven’t gotten to intermediate, overrun, or OD just yet but thinking I should shoot for 0.045 to 0.050 on a 4 clutch intermediate and the others are going to be what they will as long as they aren’t too tight which I doubt.

[@nickstransmissions]

Your forward clutch is a bit loose - I'd put a direct clutch steel plate to bring it around .050 or so; direct is fine. Run intermediate to .040-.050...Overdrive pack is not adjustable so as long as you have clearance you should be fine. You can check my clearance for reference but, provided you're using factory spec frictions and steels in terms of their respective thicknesses, you'll be perfectly fine.

[@christophersanders5007]

I reused my aluminum pistons as well on my early model 4L80E build. I tried using the bonded pistons that came with the rebuild kit, but the bonded pistons sit up too high, and I could not compress the spring cage down enough to clear the spring cage snap ring. When it came to the overdrive clutch seals after several tries at trying to install the seals myself I just gave up. I took my overdrive clutch to a trans shop that had the tools and experience to install the overdrive seals. They got the job done in 5-minutes. They tried to say no charge, but I flip the builder who did it a $20 bill for doing for me anyway.

[@nickstransmissions]

It took me about 10 or so 4L80Es to get to where I can install those seals quickly like you see me do in this video...My first attempt took like an hour, lol!

[@rksg2003]

Nick thank for this series its been a few years since I did a 4l80e and you are my go to videos for transmissions... Nick can you reccomend a brand for an inline filter? Thanks again man!

[@nickstransmissions]

You're welcome, Bee Gee and thank you for watching. Unfortunately, I don't know of any inline filters or have any direct experience with any so can't say however Amsoil or other similar performance vendors may have something along those lines.

[@ganeshramprasad4817]

what causes a 4l80e to stall when in reverse after a rebuild? Forward works perfectly, but only in reverse it stalls.

[@nickstransmissions]

Hi Ganesh, there could be a serious bind in reverse resulting from too-tight an engagement between the band and front planet, malfunctioning TCC or TCC lock up causing the converter clutch to apply when put into reverse or something engine-related that doesn't present when in drive due to differing load 'forces' being put on the engine in reverse compared to drive.
Interesting case - please let me know what you find out what's happening once you get it fixed!

[@danielgosnell5090]

were can i buy the lip seal tool like yours??

[@nickstransmissions]

Hi Daniel, thank you for watching...Check out WIT Performance (Whatever It Takes Performance)...They sell them and can be found on eBay.

[@Roscotech]

I wanted to ask your opinion on something I am trying. With my pump installed (it’s a different pump than the original bc that one was in very bad shape) and the play in the input shaft at the small snap ring (that secures the input shaft to the front planet) accounted for I had a little more than 0.050 of front end play. The only pump spacer I had was the red one (0.073-0.077). I did find a 0.030 steel shim (I built a LOT of rear ends) that I put between the pump stator and the factory plastic shim. I also had a 0.019 shim that fit perfectly under the thrust bearing under the front planet. I looked to make sure the planet gears did not protrude above the ring gear (it did not) and then air tested the overrun clutch to make certain that the sealing rings were in fact able to seal and that the rings were still well within their sealing area. This set up netted me a perfect 0.005) of front end play. I your opinion is that something that might possibly give me an issue? Everything spins smoothly and freely, really nice in fact. And factory front end play is (as I’m sure you know) is 0.005-0.025.

[@nickstransmissions]

What is your rear end play?

[@Roscotech]

Rear end play is tight. Maybe 0.005 tops. It’s a bit more involved to check as you know. It’s the same as it was before disassembly as I made no changes there. I had the reaction carrier machined to clean up the low/reverse band surface. The previous builder had put a wide bushing in the rear of the case which is still in excellent condition and the only bushing I didn’t replace. It’s basically (low clearance) nothing yet still spins very freely. There is about 0.025 to 0.030 “float” between the reaction carrier and the bottom of the center support and my intermediate clearance is right at 0.040. I also made a rear band pin length checking tool from a late model servo cover (I saw an article about this) and used the Sonnax adjustable apply pin. Really pleased with how that worked out.

[@nickstransmissions]

You need ~.005 greater clearance in the front (net of the input shaft snap ring) than you have in the rear to prevent potential case binding as parts expand under heat. End play in the front has to be measured while the rear section loaded forward. Rear unit end play spec is .005 -.025 and front is .004-.022.
I'd install a slightly thinner selective washer behind the pump to give you somewhere between .010-.012 end play up front.
My targets have always been .007-.012 in the rear and .010-.017 in the front and that's for all 4L80Es that I build.

[@Roscotech]

Okay thanks Nick! I didn’t have the rear loaded when I did my front check! That’s very helpful that you pointed that out. I’m not in a big hurry on this one so I will go back over everything and get it right.

[@nickstransmissions]

You're welcome, Ross!