I have a 2002 Ford F150 single cab short wheelbase it's 4wd and has the 5 speed with 33s. I'm only averaging 10mpg and the truck runs fine. Anyone know what this could be?

 

Well in my expert opinion I'd say you have a truck. Get used to it lol

 

That sucks. I have a 4 wheel drive auto SCAB w/ towing package and I'm getting 14.5 average. Not sure what size my 265s amount to, but still, 10 MPG?

 

Have you adjusted the PCM to the different tire size and read the mileage thread:
https://www.f150forum.com/f2/ultimat...133049/index3/

 

31

 

I get a lil better than that with my 01 SCREW, 6" lift and 35's...

 

If that's the case he should definitely be getting better than 10 MPG. When I had my 250 I went up to 285s and only lost 1 MPG.

 

so my 265/70/17 are 31's? and I get about 13 mpg in my 03 screw fx4 wit tbars cranked an 2" block in back

 

This is what I'm betting on.

You can check how much you are off by using a GPS. Zero it with your Odometer and run it for 100 miles (gps miles). See what you get.

Get yourself an SCT-X3 to reprogram it. I believe 33's are around 630 revs/mile.

 

265/70/17 = 31.6x10.4/17