unbastardoloco

I am in the process of reshimming the main and counter shafts on my T56 as part of a swap from LT1 to LS1 input shaft and front plate. Unit is used with unknown miles, aside from reverse synchro and shift fork pads, all internals appear to be in overall good shape as far as my novice eyes can tell.

Per the service manual, I have it assembled with just the input/main and counter shafts w/bearing races (no shims), case and front plate torqued to 26 ft/lb.

The problem I’m having is the main shaft end play is out there at ~.103-105, which when shimmed to get a .002 preload, pushes the main shaft gears out of alignment with the countershaft, this doesn’t seem right. I have a couple photos below.

Any experienced folks have some advise on what I may be doing wrong, things to check or if this looks like it’s within acceptable tolerances?

AMP-D

Do you have the pocket bearing race installed inside the input shaft?

unbastardoloco

Sure enough, that’s missing. Thanks so much, I’ll get that in there and report back!

AMP-D

I'm sure once its pressed into place, your shimming issue will be resolved.

unbastardoloco

Finally was able to check endplay and was a much more reasonable .035. Thank you again, how did you know right off the bat to pinpoint this bearing?

AMP-D

Figured you purchased a new input shaft and whomever you purchased it from didn't press a race into it before shipping it. Some suppliers offer the race installed with the input shaft but most do not.