GM 6.0 gear searching.....

APT wrote:
4.10 will just mean 2200rpm at 65mphh is now 2420rpm. That will allow some situations where 5th gear will hold longer. However, 4th gear is now 300rpm higher. I'm not convinced that will be helpful enough to justify $2000-3000. $600 for a custom Black Bear tune will not likely provide much more increased torque at 2200rpm (less than 10% of gearing), but I have heard it greatly improves normal shift programming.

Changing gears does more than simply change the cruising rpm though.

To make it simple...say you are putting out 100 ftlbs of torque, through a 1:1 ratio gear in the transmission with a locked converter, with a 3.73 rear.

That is 373 ftlbs to the axles.

Change to 4.10's.

You are now at 410ftlbs feeding the axles.

So you gain 300rpm to put you closer to the power range you want, and you gain 37 ftlbs to the axles. And this multiplication happens across the entire rpm range.

Say you open the throttle more going up a hill and you are putting out 200 ftlbs or torque.

3.73s : 746 ftlbs
4.10s: 820 ftlbs

74 ftlb difference...gears MULTIPLY the torque to the next thing behind them.

This is a very simple example to show how gear multiplication works for those that don't know.

If you can deal with the rpm, there is no cheaper way to boost torque to the rear wheels in gas truck.

With a engine that makes power at higher rpm like a 6.0, and a double overdrive 6 speed, I would add more gear in a minute! Doubt it will affect towing gas milage, might even help. But when I tow, I worry less about mileage and more about the truck doing what I want.