CW00BlackTA

iTrader: (31)

Did the rebuild myself with all the usual parts including a new 1-2 synchro, billet keys, bronze pads, carbon blocker rings, steel 3-4 shift fork. Followed the manual to the letter. Also installed a new twin disk clutch.

On first test drive everything seemed to be working perfectly until I shifted to 3rd gear. It acted like there was no synchro at all, just grinding. Clutch needed more bleeding so limped back home and did that. Second drive it felt a little better but still not right. Right now I have 30 miles on it and everything is still good except 3rd. If I shift slow enough, it won't grind. I'm hoping with some break-in miles it will start to work properly.

Anybody else have this experience? Advice?

Thanks.

LS123

iTrader: (11)

Did you have issues with 3rd gear before the build? Did you replace the 3-4 synchro? Did you inspect the engagement teeth on the 3rd gear? What shifter do you have? I can help you better if you can answer these questions.

1fastkingcab

there is a TSB out to replace 3rd gear while you are in there, like LS123 said Did you replace the 3-4 synchro? Did you inspect the engagement teeth on the 3rd gear?

CW00BlackTA

iTrader: (31)

No, no issues before the rebuild with 3rd. I did not replace the 3-4 synchro because a careful inspection showed the teeth were all in good shape--the synchro teeth and the gear teeth. I have the stock Hurst shifter.

I did talk to a guy at the ship where I purchased the parts and he said sometimes the blocker ring doesn't engage correctly with the mating contact surface. Sometimes it corrects itself after some break in and sometimes they have to pull the synchro and scuff up the contact surfaces with 120 grit.

CW00BlackTA

iTrader: (31)

TTT for Sunday.

thesource

iTrader: (60)

Sometimes the cone on the gear can get glazed. When that happens, you need to rough it up a little bit. Its rare to see in the T56 but I have ran across it several times over the years in rebuilding manual transmissions in general.

CW00BlackTA

iTrader: (31)

OK, thanks. I'm going to drive it for a week and put another hundred or so miles on it to see if it will start working properly. If not, next Saturday afternoon I'll get to pull my tranny again!

6speediroc

iTrader: (5)

Did you ever get your 4rd gear issue sorted?

I have the exact same issue (to the letter) and spoke with TheGearBox guy today who said to scuff 3-6 gear cones with 80 grit..
I remember they were mirror like finish when rebuilding.

https://ls1tech.com/forums/manual-tr...r-rebuild.html