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Old 10-18-2013, 09:23 PM
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I am rebuilding my transmission and my question is after installing 5 lined & 5 steel in both the forward and direct clutch packs i have excessive clearance / piston travel if i install an extra steel (.075) at the top before pressure plate it brings clearance down to approx .060 Is this ok to assemble like this ? Frank This is a 4L80E 1995

Last edited by froggy1938; 10-18-2013 at 09:36 PM. Reason: Correct Spelling
Old 10-19-2013, 01:41 PM
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0.060" is fine for the forward and direct. A good rule of thumb is around 0.010" per friction.

If you added an extra 0.075" and your clearance is still 0.060" that is weird, I think. That means your clearance without the extra steel is 0.135". Are you using the correct thickness steels and frictions? Did you remove the wave washer?
Old 10-19-2013, 02:58 PM
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I just did a couple of 4L80's, had the same problem in one of the direct drums.
It didn't have a waved washer, it did have a coned washer.
I left out the coned washer and replaced it with 1 direct and one forward steel (IIRC), I was told to put them on top of the piston (bottom of the stack) and to be careful that the bottom one couldn't slip into the groove at the bottom of the drum.
Old 10-19-2013, 04:50 PM
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I used one thicker TH400 steel in my intermediate, and a thicker wave steel in the forward to get the clearances down. I'm using a 6 disc direct setup and the clearances were a tad loose but I'm not too worried about it. I doubt I'll ever do a WOT 2-3 shift, it never sees the track. I was most worried about the intermediate. Forward only applies when you engage drive, so I feel like its clearance is not critical.
Old 10-19-2013, 05:31 PM
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Typing from my phone in line at a Chipotle so not the most detailed response, but your forward clutch clearance can be relatively tight. Shoot for about 0.60" on the directs. Ditch the wave plate and add 6 Hi Energy frictions and 6 steels and your clearance should be near ideal. Drill a .030" bleed hole in the edge of the drum as well, to prevent potential centrifugal apply.

Also, leave OFF the inner seal on the DRUM NOT the PISTON. Keep both piston seals. Ditch the drum seal, ditch the second from the top seal on the center support and plug the passage to the right of the intermediate piston apply passage on the center support with a 3/8" cup plug in the case. This will dual feed those direct clutches. At that point, you pretty much have a clutch pack you're not likely to kill if done properly.
Old 10-19-2013, 10:28 PM
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Thanks Guys I was worried because book says there should be .119 piston travel on both drums ,Where i have .060 clearance (wich shold be the same measurement ?) Right ?. Frank
Old 10-20-2013, 02:15 AM
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For you, pay less attention to piston travel distance and more on top friction to pressure plate clearance.

I just noticed in your first post you mention something about putting an extra steel on top. DO NOT DO THAT!! VERY BAD! Under no circumstance should a steel make contact with the pressure plate, the clutch pack should always end with the friction on top. If you have to add an extra steel, put it at the bottom with the first steel. Double them up.
Old 10-20-2013, 08:31 PM
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?? The steel on top is splined to the drum just the same as the pressure plate there is no friction between them A steel on top just moves the pressure plate down the thickness of the steel plate weather a friction is gripping against a steel plate or the pressure pate makes no difference weather its on top or on the bottom the steels do not spin in the drum And the pressure plate is no more solid than a steel plate when compression occures Its just like a thicker pressure plate !
Old 10-20-2013, 11:10 PM
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Honestly your post is extremely hard to understand and I'm not entirely clear on what you're trying to say, but listen to me: You do not put a steel at the top of the clutch pack. A pressure plate should only be making contact with a friction, NOT a steel. If I knew what you were trying to say, I could give you a more technical answer, or rebuttal.

You start the pack with a steel on the bottom, end with a friction on top, always. You are the one coming on here asking if it's okay to assemble it like that. I'm the one on here with the experience to tell you no, it is not okay to assemble it like that.

Follow the advice I've given you the last few posts and do the mods I suggested and you will be just fine.
Old 10-21-2013, 12:31 AM
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Originally Posted by eLiT3SnIpEz
Honestly your post is extremely hard to understand and I'm not entirely clear on what you're trying to say, but listen to me: You do not put a steel at the top of the clutch pack. A pressure plate should only be making contact with a friction, NOT a steel. If I knew what you were trying to say, I could give you a more technical answer, or rebuttal.

You start the pack with a steel on the bottom, end with a friction on top, always. You are the one coming on here asking if it's okay to assemble it like that. I'm the one on here with the experience to tell you no, it is not okay to assemble it like that.

Follow the advice I've given you the last few posts and do the mods I suggested and you will be just fine.
I think what he is asking is, what's the difference between having the last friction contacting the backing plate instead of having it contacting the extra steel? Seems to me that it doesn't matter. But if it were me, I'd put the extra steel against the wave steel.
Old 10-21-2013, 10:52 AM
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Ok Let me explain it better By the way I started overhauling automatics in 1955 The original hydramatic, Twin Ultramatics Cast iron powerglides Torqueflytes fordomatics up thru Jetaways & slim jims Then i put in 20 yrs as a VW service manager so i am more or less just asking for second opinions . This 4L80E is a transplant from my 1977 Winnebago That i installed with 1995 5.7 FI eng and complete wireingharness and control unit along with speedo assy . due to a new rubber cooling hose getting a pin hole and slowly loosing fluid on the PA turnpike I burnt the clutches before i could get off the road After temp repair veh went another 500 mi before starting to slip to bad to drive. So i am rebuilding again . It worked just fine with the extra clearance in clutch assys . Ferocity02 understood what i was trying to say What difference does it make weather the last friction plate contacts another steel plate or the pressure plate The steel plate contacting the pressure plate without the softness of a lined plate would be the only difference There is no friction between the steel plate and the pressure plate Correct ???
Old 10-22-2013, 08:28 AM
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Putting the extra steel against the pressure plate or on the bottom is irrelevant. If there is a waved steel, then use it as it takes up some of the shock of the engagement. If you still have excess clearance, then install the extra steel on top of the waved steel. If you can add as extra clutch and steel, and are not going to use the waved steel, then do so. Clutch clearance should be .050" - .080" for the direct. Leaving off the 2nd sealing ring on the center support is a good idea, as is the cup plug and the .030" bleed hole in the edge of the drum. DO NOT leave off the leave off the inner seal on the drum, as this slows down the release of the piston on the 3-2 downshift. We used to do this many years ago, but stopped because of this problem.
Old 10-22-2013, 11:25 AM
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Dana, that's weird as I have never experienced that at my last job at Jake's or with the current builds that I do. I always recommend taking off the inner seal of the direct drum and continue to do so. Never had a single problem relating to it either.

As for the pressure plate-steel topic, I shouldn't have jumped the gun. It won't hurt anything per se, but in the case of something like the forward pressure plate where there are oiling grooves specifically for oiling a clutch, why defeat the purpose of putting a steel there? Also, I try to keep things as close to stock design as possible, in a sense, and I know the majority of other builders do as well. Ever torn down a transmission and seen a steel on top? I haven't.
Old 10-23-2013, 09:35 PM
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Opps, Sorry guys did not intend to start an argument . I added the extra steel on top of the beveled steel at the bottom, then a steel / lined /steel etc, both units ended up with .083 clearance If it stops raining ill install it and let you know how it works Frank
Old 11-10-2013, 04:30 PM
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Turned out fine 300 mi road test no problems Thanks for input Frank



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