What can I expect to get in mpg on a 07 5.9L 4X4 with 4:10 rear end. It does have 35" tires with 20" wheels and no real lift. Should the rear end be changed out to a 3:73? How much would that cost? Or should I be looking at a gear vendors overdrive.

This truck is completely stock without any of the goodies.

 

That all depends on your (R) foot! The mileage on these trucks have always seem to be all over the place, since day 1.

My brother has pretty much the same truck except an 04.5 and he sees roughly 17-18 in the highway and 14-15 in town. He does have a chip on it.

Now on my 02 I had a chip, 110hp sticks, FASS, and some other goodies and it dyno'd a little over 400 ponies and 900ftlb of torque and I got in the low 20's consistently. I also had 35's, 3.55 gears, and a 5spd.

My current truck in my sig, since moving to CO I get on average 23. When I lived in CA, I got 19-20.

 

 

id say high teens if ya keep your foot out of it, instead of changing gears i would recommend getting programmer like a smarty that you can change what tire size you are running and it will update your speedo and it will give ya better mileage

 

Enjoy the forum.

 

Have Fun

 

My 05 with 33's gets 15 average. On the highway at 78mph 12.5mpg or so the computer says probably not that good. This truck won't take my smarty(software unknown?) I use on my '05 pull truck so that is with stock programing and 4:10 gears.

 

Welcome GDief, I just put on 35's and haven't run a through a full tank yet and haven't had my speedo recalibrated either, so I can't tell you the mileage. The lie-o-meter says 14.9 if that helps you. I have 3:73 and was wondering about the 4:10 gears as my RPM has really dropped since the 315's went on, I tend to keep in tow/haul more now when cruising in the city.

 

 

Welcome to DB. Remember with 4.10 gears and 35" tires you basically have a final drive ratio of 3.55. Now you probably won't get as good of mileage as if you changed to 3.55 gears and stock tires, but you won't be too bad. High teens low 20's are doable still I would think. But like it was mentioned already, you ,as the driver, are the single most important factor regarding fuel mileage.