Hi. I am having some problems with my t5 tranny. I bought a 91 firebird with stock 305 and t5. The car had 250,000 miles on it. I test drove it and it shifted just fine with no problems. I did an engine swap to a mild 350, and kept stock t5 tranny. I drove it about 60 miles the first day with no problems except small whine in 5th gear. I installed new clutch kit, pilot bushing, TO Bearing, etc. The more I drive it the more different things it does. 1st thing was it would pop out of second when downshift from 3rd. then started poping out all the time upshift or downshift. 2nd: 3rd and 5th gear both have a whining small grinding noise while driving. 3rd: reverse used to be no problem, now I have to wiggle the handle a little until it finally falls in. 4th: Started grinding when downshift from 4th to 3rd. 1 week later now grinds upshift or downshift from 3rd to 4th and also downshift from 5th to 3rd. I cant downshift at all into second, have to take turns in 3rd. Sucks!!! I have been driving 1st to 3rd to 5th for about a week now so I wouldnt tear anything up hopefully until I can figure out what to do. Im sorry this post is so long. Please Help. A friend of mine said it could be because I didnt bleed my clutch. ??? IDK. There is also small ticking noise when in neutral and clutch pedal out. Noise goes away when push in clutch. And sometimes I will start the car up and it has this loud metal clinking noise coming from tranny. Sounds like a bell clinking, or kinda lika a chainsaw tinking. I can shut car off and start back up and it wont do it any more. Again sorry so long. Please Someone Help. THANKS IN ADVANCE...

 

From what I have learned the T5 is not rated for more than 270ftlbs of tq. A lot of us do more including my self but with 250000 miles on it you may have killed it.

I am in a similar boat I am afraid that I will kill mine when I install new heads, your options are simple

1) Get another T5 go for a world class hope it holds
2) Rebuild your T5 and hope it holds
3) Get an upgraded T5 probably over $1000
4) Do the T56 swap and have no more problems

 

Ok thanks for the info. I wasn't sure what was happening. I thought I had maybe (hopefully) installed something wrong. I think I'm just gonna put a TH350 in it and be done. Thanks again.