4L80E build

P10crew · May 14, 2019

Direct clearance dry
34127A
(5) .090 steels
(5) .080 Frictions
.176 pressure plate
.105 clearance

34127A
(5) .077 steels
(1) .075 used steel
(6) .080 frictions
.176 pressure plate
.009 clearance
The math don't add up but it's pretty close.
Kinda hard for me to tell when I start compressing the wave.

P10crew · May 14, 2019

By the way Wit is so sure I have the correct 34127A they are sending me 3 from Houston free.

clinebarger · May 14, 2019

Alright......I found my TH400 binder with all the handwritten notes from over the years

*GM 8623113 is used in combinations of TWO or more. (34127A)
*GM 8623851 is used as a single Wave. (34127) Has more pronounced waves.

100% my mistake on this one bud!!!

Just so you know.....You can run either of the above steels directly against a Friction! You do not have to isolate them like with the spring steel 4L80E Waves!

P10crew · May 14, 2019

Well that should give me more options. Thanks

P10crew · May 15, 2019

CLine there is 2 different ways I can make this work

The v steels are the .077.
.063 clearance but can I run a friction against the pressure plate?

.053
Bottom is the wave both pics.
I can also gain another thou each by replacing the new .077 new steels with good used ones.
All tests were dry.
All I really did is get rid of a .090 steel and replace it with a .80 friction.

clinebarger · May 15, 2019

Yes....You can run a friction against the Pressure Plate.

Do you have enough frictions to run Six in the Direct?

I would check the clearance WET.....Then proceed with whichever count/stack you want.

P10crew · May 15, 2019

Yes I do. Long ago you reccomended that I get 1 extra HE. Will do and thank you.

P10crew · May 15, 2019

Now I'm on to the forward. .010 - .012 per friction in this as well? Any tricks or secrets you can share about this assembly? Lol
The sonnax hub came with a roller does the black side go toward the drum or away?

Stock wave?

clinebarger · May 15, 2019

I reviewed the Sonnax Forward Hub directions on their site.....They show the correct orientation.

The bearing that sits on top of the Forward Drum orients Black race down.........

clinebarger · May 15, 2019

If your not backing trailers for long distances or often.....You can set the Forward Clutch clearance as tight as .020"......Though I would shoot for .030"-.040".

The Forward Clutch doesn't see 1/4 the cycles that the Direct Clutch see's.....So the OE Spring Steel wave doesn't have a tendency to break. I've only seen it once on a high mileage Sweeper truck.

Interesting fact......200-4R units have NO Forward Clutch Clearance per se. They run tight against the wave plate & are forced to overrun in reverse with some drag. Powerflow between a 200-4R & 4L80E are pretty similar.

P10crew · May 15, 2019

Cool cool .
Since I used some of the forward steels in the direct I may have to order steels but we'll see what happens. When I reuse good used steels should I like lightly scotch bright them or leave them alone?

Thanks

clinebarger · May 16, 2019

You can leave them alone as the Forward clutch is not Dynamic.

P10crew · May 16, 2019

In an attempt to find an accurate method of measuring clearance in the forward I came up with this.

Lapped the burrs off the hole end of a full set of feelers.
Assembled hub and snap ring. Then reached in with a pick to push the feelers outward. Works pretty well!
As left .030. Having to use a pick you loose the sense of feel but doable none the less. This could be a 30 second operation with a ground ring of a known thickness that sets on the piston and a height gauge. Non the less i'm calling it .030"

P10crew · May 16, 2019

Cline do you typically need the sonnax 34298-078 Front forward hub +.015 washer?

clinebarger · May 16, 2019

Originally Posted by P10crew
Cline do you typically need the sonnax 34298-078 Front forward hub +.015 washer?

Sometimes! But in your case.......The Sonnax Forward Hub is +.025". You may need a tinner selective at the Stator.

P10crew · May 16, 2019

Thank you!

P10crew · May 17, 2019

More questions
Other than the holes that are yet to be drilled in the plate can I drill the remaining holes in the pump and overrun to the size's that ck calls out in the instructions?
What should front end play be? I know you posted that but looking back I can't find it..
Over run clutch clearance?
OD clearance?
Can you explain what the turbulator feature does for the over run and of steels? I assume that's what the holes are.

clinebarger · May 17, 2019

Go ahead & finish building/modifying the sub-assemblies.

Turbulator steels allow ATF to flow through & better cool the clutch pack when overrunning. Some designs have the holes/slots in the friction plate as well as the steel.......Allison 1000 for example.

There is no conventional means to adjust 4th Clutch or Overrun Clutch clearance, Just make sure the steels & frictions are close to the correct nominal thickness.....And they DO have clearance.

Front End-play: .002" to .005" LOOSER than Rear Unit end-play......If you were to set the front the same of tighter than the rear, The rear unit would/could thrust into the front & that would be bad as the front selectable is not designed for heavy thrust loads!!