TrakDay

iTrader: (7)

Well... I am beginning to think my tranny is not going to be one of the ones that holds 700rwhp/trq like some other stockers do. Right now the car is making 600+rwhp and 500+trq, and it feels as though the tranny is starting to have some issues. Getting in and out of 4th gear is no longer simple and smooth. And for once I think I am going to fix something before it breaks all by itself! All of this is for the M12 T56 Tranny in my 04 Procharged GTO(heavy).

So my question to you guys is what should I replace? I know very little about Tranny rebuilds and would most definately have someone else go ahead and rebuild it for me. I am not trying to go broke while fixing/strengthening this thing, so I would most definately like to keep it reasonable. The goal for the car is 750+rwhp when I build the motor and thats without spray... Oh and while the tranny is out should I go ahead and make the clutch swap to something that will be suitable to hold my power level goals? Which clutch would you guys recomend?

Any help is appreciated! And also any recomendations on who does nice rebuilds would be great! I spoke to Joe at T56Rebuilds.com and he was very nice and helpful.

Thanks ahead of time!

sgarnett

iTrader: (1)

I don't think you can build an M12 to the same strength as the M6. That's partly because the Viper output shaft can't be installed in an M12, and partly because of the lower first gear. G-Force may have some beefier options, but that won't be cheap.

I'm not sure you're really describing a torque-capacity failure, though. It sounds like you have some synchro issues, possibly due to the clutch not releasing fully.

My M12 was built by Rodney at RPMTransmissions. FWIW the internals were cryo-treated which might improve durability (can't hurt) and polished (which improves the shifting). I'm happy with it and RPM, but I've got less power and less weight, so I can't tell you the M12 will or will not hold up in your application.

ninetres

iTrader: (35)

Check the sponsor T-56 rebuilds.....LS1joe.

He did my buddy Tony's and it is awsome.

TrakDay

iTrader: (7)

Well I changed the fluid and it feels much better. Only time will tell. I am going to the track on Sat. this Wknd, so I guess we will see how it does.

If it lets go just after I make my first 10second pass I could care less!