Mike44138

iTrader: (3)

I'm trying to verify that the input shaft in my trans is the correct shaft. Trans is from a 2000 Trans Am. I'm trying to avoid dismantling the trans and Im looking for a quick method to verify. Anyone out there with their LS1 T56 out that can give me a measurement of the length of the input shaft while installed in the trans. I'm looking for a measurement from the front plate of the gear box to the end of the shaft.

I'm including a link to a couple pictures from another post, and a link to the history of the problem I've been screwing with from last year. The Pic in this message is my trans.Can anyone verify this measurement??

At this point I've replaced the flywheel, bellhousing, trans mount, engine mounts, pressure plate, clutch disc, and had the input shaft shimmed... not to mention replacing numerous slave cylinders, some lasting longer than others.

yes... my car is still blowing up slave cylinders.

Here's the history on the problem...

https://ls1tech.com/forums/showthrea...slave+cylinder


https://ls1tech.com/forums/showthrea...+shaft+lt1+ls1

Mike44138

iTrader: (3)

t.t.t... here's the pics of my input shaft

Mike44138

iTrader: (3)

Just a note for anyone else that might be running into these problems. I'm confident I finally corrected the problem. It appears that when the dealer had the transmission out over 3 years ago to correct the "jumping out of 3rd" problem the shop they subbed the work out to screwed up major. They either put the wrong trans back in the car, or they put the wrong input shaft in my trans. End result was a T56 in 2000 TA with an LT1 input shaft. Worse yet the number on my case that identifies the trans is 1386-017 which isn't the proper number for an LS1 T56. It should be 1386-020. Most trans shops go by this number when ordering parts, so they probably would have never caught it because measurements on new parts would be the wrong parts for an LS1, but would match the parts in the trans.

I've probably pulled this trans 5 times to replace busted slave cylinders before I finally figured it out thanks to someone else on the forum having a similar experience. Decided to check it this last time on the off chance that I could be in the same boat. Replaced the input shaft and bearing with the proper one for an LS1 and did a synchro rebuild and things are running smoothly...

Like I said, just hoping to save someone else the hell Ive gone through with this car. Anyone with a trans repeatedly breaking slave cylinders who has had the car in the shop for trans problems would be wise to take a quick measurement of the input shaft length. It would have saved me countless hours and quite a bit of cash.

Project GatTagO

iTrader: (7)

Thanks for the update. That input shaft is definitely too short. I can measure my LS1 tomorrow if you like. I did it the other day and I think it was almost 7 inches. It makes perfect sense in retrospect why you were going through slaves. The input shaft was not in the pilot bearing so it was not supported. It was wobbling around and doing god knows what. Glad you figured it out.

Andrew

calhoon

iTrader: (6)

I would seem that the trans you had was altered incorrectly. The 017 model T56 is for a '98 Fcar, the start of the LS1 application NOT an LT1 box as you state.The 020 model is a later LS1 model but the inputs are identical for these transmissions. I agree, the shaft you have is too short , and prolly a LT1 part,but it is due to an incompetent rebuild/ rebuilder . If it had been correctly rebuilt to 017 specs, that shaft would not be there. It would seem that some one grabbed an old trans ( you said your car was a 2000, this is a '98 trans) and botched the rebuild.

chadtx01

iTrader: (5)

I went through the exact problem when I got the car. Went through 5 slaves in the first 4 months.

Here are some pics of a LS1 input shaft compared to a LT1 input shaft.

https://ls1tech.com/forums/manual-transmission/503675-pics-broken-slave-cylinder-cause.html

Mike44138

iTrader: (3)

Talk about a major screw up.... I think it was just bad workmanship by the shop when they replaced the countershaft to fix a bent 3/4 shift fork, and they threw it back together without ever noticing the difference. Maybe swapped front plates and sent it out. Either way the input shaft and synchros are in and the car runs 1000% better (imagine that). Specially thanks to everyone that provided input across the last couple months, giving me the ideas to finally solve it.