Need HELP!! Manual 5speed to LS1 M6 Tranny Swap

[blown_n_on_fire]

I have a 2004 Chevy Joe Gibbs Silverado. It is the 4.8L supercharged with the stock gm 5speed tranny. I am wanting to put a LS1 M6 tranny it and change my ring and pinion from a 3.73 to a 4.10. I am wondering if anyone could tell me the gear ratios of all 6 gears in the M6. I also was wondering if anyone knew if an M6 would bolt up to the 4.8L or if It is even gonna be worth my while to do this modification to my truck??? I just always hear LS1 guys saying the Gibbs trucks would be way bad if they had a M6 6 speed instead of a 5 speed. Any help anyone could give me would be greatly appreciated. Any ideas on more speed and power mods for the Gibbs trucks??? I am having trouble finding underdrive pulleys and stuff too??

[oneBADDz]

First 2.97:1
Second 2.07:1
Third 1.43:1
Forth 1.00:1
Fifth 0.80:1
Sixth 0.62:1
Reverse 3.28:1

[oneBADDz]

Oh yeah, it'll bolt up

[oneBADDz]

Actually, I gave you the wrong numbers, those are 93 t56 only, here's 94-02
2.66:1 first
1.78:1 second
1.30:1 third
1.00:1 fourth
.74:1 fifth
.50:1 sixth
3.28:1 reverse

[oneBADDz]

For proper fitment you really need to get one from 98-02, there are slight housing differences

[blown_n_on_fire]

Hey man thanx for the #'s... Do you think this would be a worth while mod for my truck? thanx again

[oneBADDz]

Oh yeah it would, not only would you have lower gears for off the line, you get an extra overdrive. Do we even need to mention the cool factor? It's a win win

[30thbird]

BTW The first ratios are GTO ratios too and would also work if you want them.Minor conversion but basicly the same install as an LS1 T56.