I am contemlating a 6 inch lift and a set of 35 inch tires. With a 3.55 rear end and a stock motor how much fuel milage will I loose. bone stock I am getting about 17mpg. I have heard my milage will get as low as 11 mpg.

can anyone shed some light on this.

 

I received about a 2-3mpg hit on the freeway and about 2mpg hit in the city. I lost most of my highway mileage because of how high I went up. I monitored my rpm's after I installed the 6" and was riding on stock tires, so it's safe to say the tires are not what kill your highway mileage (it didn't really go down after mounting the tires). Which engine do you have, those 3.55's are going to be hurtin w/35's. I'd definitely regear if I had anything worse than these 3.73's. I did not lose much mid-range power at all, low end I did and top end I did. I still pull very hard from 35-40mph.

 

I get 11.02mpg with my 35s

 

I got 15.5 mpg on my last truck with 35" Mud Grapplers and 3.73LS.

Granted, I was running the Edge Level 3 tune with 93 octane, Flomaster SI/DO, and a K&N Drop-in filter.

 

I forgot to mention that I am driving a 2006 supercab 5.4L

 

I'm assuming you have a 4wd, I'd get an Edge tuner first and then see how it rides. It will also correct your speedometer, odometer, etc.

 

I'm averaging about 11.3mpg city/hwy combo driving.

When the truck was stock, I NEVER saw better than 14 mpg, so the difference was immaterial when you factor the enjoyment of having a lifted truck.

 

10.5 to 11 Mpg on average... 6" of lift and 36" tires you are gonna take it in the behind at the pump its just the way it is. But I can say this it beats riding in a regular ride anyday!

 

For those who didn't have their speedometer recalibrated, you need to add the difference in miles to get a true reading. from my stock 255/70/17's to 305/55/20's, I am off a 10th per mile or 1 mile for every 10. If you fillup at 300 miles you should use 330/fuel used to get true mpg. I was getting 18-19 before and now I get 17-17.5.

 

I'm getting 15.3 with my 37's 5.4L 4.56 rear end.

 

With the cruise on at 55-60 under good wind conditions my lifted 04 5.4 3.73 gets 21mpg on 35's and 12mpg city...the JBA Headers, e-fans and U/D pullies help achieve that i'm sure.

Norm

 

I get 11.5mpg with my 37's and my 6in lift with a 3in body lift..im running edge programming 2 and dual flowmasters

 

Raising the truck will increase the drag coefficient dramatically. Putting heavier tires/rims will decrease the mileage quite a bit. Increasing the diameter of the tire will possibly increase the freeway mileage and lower the town mileage, everything else remaining equal.

I have seen several studies showing that on a stock two wheel drive truck you can increase mileage approximately one mile to the gallon by plastic sealing the gaps in the frame etc. Sorta like a tonneau cover but on the underside. Raising a truck increases the wind resistance under there, so you may lose a mile per gallon just from the increased drag under the ride.

And as has been posted, if you don't adjust the speedometer to your new tire size the numbers you get will be off by the amount you vary the tire size. Increase it ten percent; your data is off the same ten percent.


If you raise a 2 wheel drive you will lose a larger percentage of mileage than if you raise a 4 wheel simply because the 4 wheel is already higher and already taking the hit for higher and bigger rims/tires.
If you raise it and increase the tires/wheels and do not swap the gears to bring it back into the normal range you can take a serious hit to the mileage.
I have seen various people’s trucks drop as much as 50% of their highway mileage, and this is with the numbers adjusted for speedometer difference.

Lifting a truck is something that you do because you want to. It is hard on the resale, hard on the drive train, hard on the suspension and death on the gas mileage.

Not to say those that want to do it shouldn't. It's their truck.

But as a mod, it can be as expensive as a blower over the course of a year or two.
It's not a minor mod. And possibly the most expensive mod you can do to a truck, counting cost, upkeep, resale drop.

It’s like the old line, if you have to ask, you can’t afford it.
Chris

 

Yep - i get about 11.0 with my 6" + 3" bodylift and 37's muds...

and that's with a camper shell!

 

i get anywhere from 10.5 to 12.5 MPG with my 6" lift and 35"s. However when i was stock i got 11-12MPG. I dont know why but my truck has never gotten better than 12.5mpg..