I'm getting about 13-14 right now in my light *** truck, so get ready to **** and moan about that expensive *** gas!!!!! I finally talked my company out of a work truck and gas, so I'm only filling up about 1 every 2 weeks now. I still take it out every other night to run the crap out of it though.

 

wont be no complaining here until i go on a trip. im spend $50 + on a fill up right now. i just hope it will be worth it to do the swap

 

what am i doing right? my ecsb 5.3 gets me 19.5 when i treat it right, which has only happened once. im sure i could do better if i was on the 3.42's. that was all freeway with the tailgate dropped. im guna have to treat it good again one last time to see what i get with the new e-fans and exhaust.

 

The best I got was about 16. That was a 330 mile trip with the cruise control set to 65. (6.0/4L80E/4.10/4x4)

 

I think gears are a bigger determinant of gas mileage than motor size. For cruising 75-80 mph, 3.73's are the best, 3.42's are a close second, and 4.10's are the worst.

 

Driving habits will have alot to do with your gas mileage. I did not loose a notice a big change with the 4:10's in my old truck.

 

If I keep my foot out of it i get 14-18MPG,With the 5.3 it was 15-19MPG.An exhaust leak at the headers will certainly effect your mileage,it did me one time.

 

My driving habits did not change one iota and I lost mileage going from 3.73's to 4.10's.