stay 3.73

 

I say since you are already crossing the line at the top of 3rd gear and have traction problems as it is, than leave the 3.73s.

I think that going to even 4.10s would only compound the traction problem and maybe force you to shift into 4th, which could hurt your ets.

 

4:56's are overkill. 3:73's are the best overall gear. 4:10's might help a lil bet, but it is going to hurt MPG.

 

I don't think you will notice the 4:10, and the 4:56 is to much.

 

The T56 has a 2.66 1st gear, the 4l60e has a 3.06 1st gear, why not go with 4.56 gears?

I have ran 4.10's with a 4l60e that gives me a 12.4:1 final drive ratio, the T56 6 speed with 4.56's would give you a 12.13.

This talk of not being able to use 1st gear is doesnt make sense. The T56 has a relatively high 1st gear when comopared with the truck 5 speeds, some of which have a 4.1:1 1st gear ratio. Gm made the T56 with a 2.66 to help with acceleration, once the vehicle is rolling the trans has close gear ratios, close gear ratios help the engine stay in its powreband better, unlike the 4l60e which is great off the line, but has horrible gear spacing and brings the engine down too far at the shifts.

I say 4.56's 100%. If I ran 4.10's with a 60e with excellent results, a T56 with 4.56's should be just as good.

If I go 6 speed, I will be using 4.10's or 4.56's depending on which tire I use.

F-body guys are constantly running 4.10's with their 26" tires, in a truck a T56 with 4.56's with a 28" tire will be no problem.

peace
Hog

 

Couldn't have said it better myself.

 

Id definitely go with 4.10.. Especially with the six speed close ratio. 4.56 will prolly give you 4 shifts in the quarter! I would keep the same ratio and do a cam!!! This will help on the power and keep from having to chance it on the gears! But if you want gears id go with 4.10s no lower.

 

Okay people, I have 4.56 gears, soon to be 6spd and 275/55/20 tires. At 100mph I'll be nearing the top of 3rd gear. If I ever run 105 in the quarter I'll be at the top of 3rd. I'd rather be at the top of 3rd than at 5000rpm in 3rd with a 60E. I see 4.56's and a 6spd being perfect....at least for my tire size and goals.

With a 28" tire at 100mph you'll be well into 4th gear, that's only 3 shifts, not 4. 105 in the quarter will put you at 5700 in 4th.

If you want to keep it down to 2 shifts (3rd gear) go with 4.10's assuming you shift around 6500rpm. Remember these are not f-body's. We run taller tires and have more weight to move.

 

i would go with 4.56 and make the truck work their r lot u can do to make that thing hook.

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I completely agree with HOG because with my old set up being a 5-speed with a 29" tires with 3.73 I pulled out of first gear somewhere around 37mph. With what I have now; 3.73 gears, T56 and 29" tire I pull out of 1st gear at 50mph. With 4.56's I should be somewhere around 40mph. I will still have a longer 1st gear with the 4.56 T56 combo than with the 5 speed with 3.73. I will be soon doing away with my 3.73 to do 4.56's.