OK I have a 2007 6.0 4spd stock tires 373 rear suburban ---CAN YOU PUT A 6 SPD TRANS IN AND /OR DO THEY MAKE A 3.42 REAR FOR THIS 2500 SUBURBAN . THANKS SO MUCH FOR CONSIDERING MY REQUEST ---DENNIS

 

You can't change physics. You're trying to move a lot of weight, punching a brick-shaped hole through the air. Nothing you do can change that. Larger tires or a 3.42 will make the problem worse, not better.

Want better mileage? Get a diesel.

 

well i can not afford a diesel right now --but has anyone used a programmer that works to give you a little better mpg towing. They all make the claim but which one works well and user friendly ----thanks dennis

 

CAFE - forces the manufacturers to do all they can to maximize MPG. Throwing a few bucks into your truck isn't going to get you any appreciable gains in mileage.

I got a Blackbear tune to improve the driveability of my truck, not to improve mileage. I reduced torque management, changed some of the shift points when in tow-haul, and a few other things. If anything, it made me more likely to drive the truck in a more "spirited" manner, and negatively impacted my mileage.

I tow an 8600-lb trailer. I get about 7 MPG while I'm towing. Unless you tow 20,000 miles a year, the cost of a programmer will be much greater than any potential fuel savings (if any).