Dana 20 Rebuild

Dana 20 Rebuild


Vero Beach, Florida
1984 Jeep CJ7 258, T150, Dana20, AMC rear, Dana 30 front, 1.5" Shackle lift, 1" Body lift. 4wd hardware fiberglass body, Stainless everything 33x12.5x15 Cooper Mesa tires, Bestop Supertop,
I'm rebuilding my Dana 20 Transfer case, and I'm just getting to the assembly part. I'm stumped on the front output shaft cover plate and shims. I've read in one place that I should lay a small bead of RTV sealant in the shim closest to the case. the TSM doesnt say anything, and chilton and Haynes don't say anything either. If you only coat the one shim closest to the case, wouldn't it leak between the other shims and the cover?
If the cases surface is smooth then no rtv needed proper torque will keep it from leaking.
Be sure to setup the right amount of shims.
Make sure to use rtv or thread sealer on the bolts that pass into the fluid chambers to prevent leaks.

They carry spray gasket stuff to make gaskets seal better and be tacky. I used it on one side of the shim as my case had a small scratch.
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Yes, in theory you shouldn't need any RTV sealant. Make sure each shim very clean before reassembly. But after rebuilding my Dana 20 I still had the shims leak. Don't use RTV. It is the same as having thicker shims. Not good! You can't measure the RTV. and even if you could it can move after assembly.
Here is what you use: Thread sealant. It will compress down to nothing and it still seals.
Here's what I used and it did the trick. It's not just a thread locker it's also a sealant:
Good for tranny and oil pan bolts too.
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Thanks for the tip, I'll pick that up today. I have to pick up a new shift interlock spring one was broke in 4 pieces.

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