Stock 17's to 20inch rims mpg difference

[swathdiver]

Hey fellas. So I have a 04 xl awd 6.0.

So I only drive this beast for long drives and family outings. Currently it has 20 inch chrome rims that the previous owner had bought. I was wondering if I go back to the oem 17inch, would I see a change in mpg's. I know alot of you guys have swapped rims in your trucks. Any feed back would be great.

Goal is to increase 2-4 mpg if possible.

A P-Metric 265-70-17 tire is going to weigh about 38 pounds. My N88, 5296 wheels weigh 30 pounds each. Stock size 20s are 275-55-20 and those tires are basically the same weight, a Defender in this size is 39 pounds. The 22" version of this tire weighs 40 pounds.

It will ride nicer and you might pick up a little MPGs since the foot print is narrower. I picked up a quarter mpg by switching motor oil from Mobil One to ACDelco. I know a guy who picked up a solid 1 MPG by switching his transmission over to Red Line fluids.

As a former President said, air up your tires for better economy and of course, find the most efficient speeds to run at.

 

[Mudsport96]

and of course, find the most efficient speeds to run at.

I find that to be the same speed as the fastest semi you can find, and stay 30 feet off the rear of his trailer.
My old 5.0 5 speed ford with 3.55s got 24 mpg at 72 mph ( roughly 2300 rpm) doing that on a trip years ago.