Changing the gears in my suburban

If it is HP and torque that you want why not just go with a different tow vehicle with the engine and tranny and rear end that will cover you now and anything in the future. Those combinations are out there but you got to lay out the bucks to get them.

Seems to me like a lot of investment for little payoff. I tried making mods to my half-ton Burb, and in the end I decided to upgrade to a 2500. THAT was the best choice I ever made, not re-gearing my half-ton.

My '01 Burb had the 4L60 and 4.10 gears. I always towed in third, and the engine was around 3200 RPM at 65 MPH. I towed down to Florida, and out to the Rockies over the Continental Divide. Engine didn't have enough power/torque to hold speed in O/D, plus I didn't want to overstress the transmission. Third is a 1:1 ratio, so the tranny was just passing the power through. Regearing to a 4.30 would provide negligible increase in power, but increase your RPMs.

And also, you still have that weak 9.5" semifloater rear, which, IMHO, is the weakest part of the powertrain. If you're towing something approaching 6,000-7,000 lbs, an upgrade to a 2500 would be your best bet.

Just my $.02.

Are you having little issues (move to 4.10 appropriate) or big issues (4.30 appropriate)? Issues getting underway? Climbing?

Thanks ShinerBock, I didn't think to look for one, I just channeled my inner nerd and made one on excel. Would have been easier, but not as fun to use that one.

Here is a good rpm calculator if you want to know what rpms you will be at in each gear at certain speeds. May help you make a decision.

RPM Calculator