LS1 F Body GM Part Number

[ad53030]

Is there more than one GM part number for 98-02 F Body T56 trannys? I know its a Tremec trans but what is the common GM part number?
Also, I have read the GTO/SSR T56 is different than the F Body LS1 T56. I understand first gear is supposed to be steeper while the other 5 are the same as an F Body trans. Are the internals (gears/synchros) really that much more expensive to repair/replace? Are the torque ratings different?

Thanks.

[jasonsnova]

i'd like to know too!

[keislerNick]

Ok I dont have gm part numbers for you but hopefully this will help you out. The 6 speed from 1993 to 1999 in the f-body cars was the same identical ratios and torque rated at 450 ft lbs the only change was this. From 1993 to 1997 the tremec part number was the 016 and this was for lt engines. In 1998 it was the same gear ratios just made to go to the ls motor. In 1999 they changed the shifter design that was the only change they made and that went until 02. The gear ratio was

1. 2.66
2. 1.78
3. 1.30
4. 1.00
5. .74
6. .50

With the gto transmission the ratios changed and if I am not mistaken the shifter setup is a bit different. These transmissions were rated at 350 ft lbs of torque and gear ratios were....

1. 2.97
2. 2.07
3. 1.43
4. 1.0
5. .84
6. .56

Now as far as the parts go you shouldn't see a difference in the cost of replacement parts.

[BlackGMC]

Here is a link I found that states some of the gear ratios. It was my understanding that the GTO T56 was similar to the Corvette, as far as gear ratios.

Transimission specs
http://www.fortesparts.com/catalog.cfm?catalogID=2

Transmission dimensions are listed below the table.

[keislerNick]

Yea the c5 corvette 6 speed trans has different ratios as compared to the gto. The top set of ratios that I posted are also the same ratio that the c5 has.