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4L80E forward clutch clearance?

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Old 07-30-2016, 01:02 PM
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Default 4L80E forward clutch clearance?

Gents,

What are we looking for on forward clutch pack clearance? The book I'm using specs .020 - .060 and suggests setting it up on the looser side of things but I've read elsewhere that you should set the forward up tighter. I'm running the wave cushion plate and using 5 frictions and 5 steels and the clearance is really loose with the .070 steels that came in my kit.

What's the right way to go here?

S.F.

Last edited by StolenFox; 07-31-2016 at 01:11 PM.
Old 07-31-2016, 06:18 PM
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Once the forward clutches come on, they stay engaged the entire time unless you move to P, N or R. They're usually on the tighter side, I'd recommend going that route. What kit did you use? .070 is thin for a forward steel, they're generally about .077"
Old 07-31-2016, 08:51 PM
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Originally Posted by SnIpEz
Once the forward clutches come on, they stay engaged the entire time unless you move to P, N or R. They're usually on the tighter side, I'd recommend going that route. What kit did you use? .070 is thin for a forward steel, they're generally about .077"
Sorry, that was a typo. Should have said .076 (actually .0755 according to my 30 yr old craftsman micrometer) so I guess they are the standard .077". Still unsure of the best way to measure the clearance on both the forward and direct clutches and what measurements to shoot for.

Thanks,
S.F.
Old 08-01-2016, 07:12 PM
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Measure between the Pressure Plate & the last Friction, The Pressure plate rest on the ledge in the Drum.....So, measuring between the snap ring & pressure plate will give false readings.
Leave the Forward Hub out while checking clearance on the Forward Clutches, You can also leave the Return Spring assembly off if it makes it easier for you.

Too tighten the Forward Clutches up.....Use a .090" Direct Steel in place of a .077". (I like .030"-.040" forward clearance)

On the Direct Clutch I use TH400 Aluminum Pistons, While omiting the Wave on a 5-Clutch set-up.....
I stack 2 .077" Steels against the Piston
Friction
.090" Steel
Friction
.090" Steel
Friction
.090" Steel
Friction
.090" Steel
Friction
Pressure Plate
This usually yields .050" Clearance which is perfect Direct clearance.

When running 6 Direct Frictions, I machine the TH400 piston to obtain the correct clearance of .060" & use all .090" Steels.



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