machpit

I recently had my car lock into 4th. I was accelerating at close to wot in 3rd, went in to 4th (no grinding) and was stuck there. I managed to get it out of 4th eventually and noticed it having a hard time synching to and popping out of 3rd. Later something was scraping 1st and 2nd (turned out to be 1/2 shift fork) Thanks to the forums here, I was 99% sure it was the 3/4th bent fork problem and happily showed them the TSB and list of others that have had the problem and had it repaired under warranty. ...They were giving me lots of trouble from my mods to the engine as well as my exhaust(none transmission related). After talking to a GM rep they took the transmission out to see if thats what the problem was. ...I went there today to see what was wrong after they called me. They didnt give a straight answer for why it stuck in 4th but said it may have been "metal filings" that had been embedded into the gears and bearings. I looked at the transmission on the table and did see alot of filings stuck to the magnets at the bottom. The weird thing is most of the filings were from the synchro part of the gears and not the synchros themselves. As for it getting locked in 4th I assume it was from the 3 pins/locks getting jammed.
The car is a 2002 formula with 19k miles on it ...with a factory hurst shifter (if that changes anything) and the 1st-6th gears all have worn sync teeth on them, reverse is fine and so is its syncro. I'll admit I have missed 2nd or 3rd a few times, but as for the wear on 5th and 6th I dont know how it could have happened, I only drop down into them to save gas and have never pushed or missed them. Anyone have any ideas or am I pretty screwed and need to buy a new transmission? The only other thing I had seen was someone saying the factory hurst was crappy and might not go deep enough into the transmission. Any advice anyone could provide would be greatly appreciated ....besids me learning how to shift Thanks ahead of time.

Camaroholic

iTrader: (1)

Check my info in this post:

https://ls1tech.com/threads/showthre...;Number=672118

Two words. Slider keys.

-Andrew

machpit

Thanks alot for the link, it may save me lots of $ ...they keep trying to sell me a new one with install for $4500 heh. Can anyone thats had the slider keys replaced under warranty please post? Is there anything you'd recommend to help get them fully covered, like relating it to the fork replacement TSB? ...Is it the jammed keys that get the fork jammed (and possibly bent later by jamming it out of 4th) in the first place? Thanks ahead of time.
-Mike

SSunset 02

You guys are scaring me... My car does EXACLTY whatt you are talking about in 4th gear. And exactly like you described - other gears are starting to act up. I however have the Pro 5.0 and a SPEC clutch...

machpit

its kinda strange, after looking at the transmision, just the syncro teeth on 5th and 6th are ground to hell. If i ground anything it would have been 2nd or 3rd. The 5/6 fork had broken plastic guides and there was a notch/groove that looked like a gear was rubbing on it. Is it possible that the 3/4 slider keys getting sheared off could have shifted some stuff enough to affect 5th and 6th like that?, maybe that grinding when I couldnt get it in 3rd was actally 5th. Oh well.. does anyone have any good sources for slighty used or new gm t56's? I know alot are converting to auto, so theres gotta be some laying around

z289899

I just had a similar incident happen except mine locked into 6th. I guess the keys come out easily and the T-56 is pretty notorious for eating up the synchros. I just got my D&D tranny today and am installing it in the morning. From what I understand they are a very good tranny and have some of the cheapest prices that I have seen. Hope that helps.
Nick