Greetings,

I'm rebuilding a '93 4T60E in a Le Sabre and have a few clearance questions. This unit wiped out number of hard parts after an output shaft bearing disintegrated and the planets in the input & reaction carriers ground the needle bearings into oblivion. As for hard parts, I had to replace the front & rear planets, sun gear & spacer, input/3rd clutch housing and 4th clutch hub/shaft.

Upon reassembly, I got as far in the stack-up as installing the driven sprocket support, and was surprised to see how far it was below the case surface. I measured .114.

I realize it'* supposed to be "slightly" below (.006 -.012), but not .114! I pulled everything out and re-reconfirmed that all thrust washers/bearings were installed and oriented correctly, and that the selective washer (a blue one, measuring .140) was present under the input/3rd clutch thrust bearing. To my knowledge, .200 is the largest selective washer available, and even if I used the largest one, I'd still wind up with the driven sprocket support ~.054 too low.

I began to wonder if the replacement hard parts I installed were the cause. I measured everything and find no more than .012 difference between old and new, which could (should?) easily be compensated for by using a different selective washer (I would think).

But, I *will* say that the origional stack-up included a mix of 1st & 2nd design components, which I wasn't able to find replacements for on a 1-for-1 basis. It originaly had a 2nd-design input carrier/front planet (no shoulder or bushing on top), and a 1st-design 4th clutch hub/shaft (no outer bearing surface on the splined end)

I was able to find both styles of input carrier/front planets, but only a 2nd-design 4th clutch hub/shaft. I didn't think that should be a problem because I *thought* they were backward-compatible with earlier models. As for the reaction carrier/rear planet, I believe they're all the same, right? The replacement input/3rd housing looks identical, as does the rear planet, sun gear, and spacer.

I tried assembling everything with a few different combinations of input carriers, but between the two, there was only about .021 difference in clearance between the driven sprocket support and the case surface when assembled.

To me, it almost seems like the 1-2 roller clutch sits too low in the case. There'* about .065 between bottom of the snap-ring and the top of the drum surface. Does the input clearance tighten up only when the final drive and output shaft are installed? I haven't installed those yet because I was worried when I saw so much clearance up top, and I'd hate to crack the channel-plate and obviously can't leave this much endplay.

Has anyone here encountered this before? Is it possible that I was given wrong planets, perhaps from a 440? (I don't even know if they're the same).

Any information/suggestions/feedback, etc is *sincerely* appreciated. Thanks in advance!

I think I found my answer. Here'* how the clearance was (.114") when I posted my question:



But, after installing the final drive, output shaft and extension housing, (and pre-loading it) the clearance dropped to .028":





.028" isn't a huge amount, but I'd still like to see it closer to .010". I worry about breaking the channel-plate knowing that it has to "bend down" .028" on the driven-sprocket side when torqued into place.

And since this is input shaft endplay, and not final drive endplay, it'* probably not going to destroy itself as a result. There'd probably just be a more noticable "clunk" going from neutral to forward gears. It'* probably best to install a thicker selective service washer, I guess...

Anyway..... mystery solved. Perhaps this post can be of value to someone else rebuilding a 4T60E for the first time.

I'm sure it will be. Thanks, Mike.