SPOAT

I went with 62 pound 34" E rated tires and saw an ~8% (ouch!) loss in interstate highway mpg.

I have a ~4% loss on rural (55 mph) roads.

Your mpg may vary. Either way, a lift/level and heavy tires will knock a large dint in your mpg.

Like the LoneWolf said.......Seriously, if MPG is your main concern then stick with stock tires or tires that are similar to stock.

Wildvan

I find this post interesting. I have been interested in the mpg to tire size, and depending on use, many may need to weigh the "looks" over mpg, trying to find that fine line of looks with decent mpg should be fairly easy with the number of lifted and changed wheels and rims. Wheather its a concern or not, the op asked a basic question, not sure why it is at times so hard on the forums to just get an answer without others telling what they should or should not do without knowing all the variables.

Rampy

17 F150 with 2.5 front level via dealership & 34x10.50-17 BFG K02's

Good MPG, great off road, all depends on what your needs and wants are...

kbass24emtp

I had Goodyear wrangler adventure 275/55/20 and went to the BFG KO2 in the same size and I noticed no difference in MPG. Biggest difference I noticed was I had more road noise that drowns out the wind noise from my tow mirrors and the BFG handle 100 times better. Best choice I have made was getting the BFG tires.

TexasRedfish

275/70/18 will clear on stock height. I ran that for about a year. Then got Fed up with the stock shocks so changed to 5100s and put on some new wheels at the same time.

Shawk

I've been a little curious as well... I see only E rated KO2's are available in the stock 18" size. I can't imagine that amount of weight not dropping the mpg a minimum of 1 and possibly 2 mpg. I'm thrilled with mpg as stock... but the cheater meter has been .6 to .7 better than hand calculated from the time I bought it. I'm wondering if those with the heavier BF's are going by computer calculated or hand calculated. I'm guessing (only guessing) that the computer will be even more optimistic vs actual with a heavier tire.

As a side note... I LOVED the KO2's on my last 4Runner but they threw rocks like crazy and chipped the side of that vehicle pretty bad. Curious if this is a problem on an F150 or if mud flaps and staying stock size will keep the rocks from chipping on the sides... (I get that all AT tires throw)

ChanD

Replaced stock 20s with same size (275/55/20 I think?) and leveled off the truck with 5100s. No difference in MPGs for me. My V8 was doing 15 before and now 15 after

techrep

iTrader: (1)

That don't look level Rampy.. you got blocks in the rear ?

SPOAT

I should add that my figures are real math.

Also, just raising the front (leveling) cut my highway mpg down ~4%. (Stock tires).

Bottom line: Heaver tires = less mpg.

Also, there is a reason the trucks come with a rake. The lowered front helps mpg.

Pecked out on my iPhone.

last5oh_302

Lifetime average with 30k km's on clock is 17.5 mpg. I changed to these new tires when truck was brand new so I don't have before numbers but with these 34.6" tires I'm not complaining.

My last two tanks averaged 20 mpg or 11.8-12.0 liters per 100 km.

I did the same setup on my last F150 and have been very happy with it which was why I did this truck the same as soon as I picked it up at dealer (although my last truck was an 05 with 5.4 and averaged 14 mpg).

Pro's- more ground clearance between level and larger tires so it's better off road as well which I do every now and again and sits nicer/looks better.

Speedometer has been calibrated btw.