bigger tires = how much less mpg?

so my stock sr5 comes with 245 75 16r and i was wanting to eventually get something just a tad bigger like 265 70 16r. what gas milage decrease should i be expecting to see? i know its basically the same diameter but an inch wider. Also, how bad was your guys mpg effected once you went bigger?

 

im thinking ko2 or just the good old stock tire for you v6 guys

 

I average around ~23/24 with Wildpeak AT3's and Method NV305's in the stock tire size unless I go like 55 on the freeway. I noticed immediately and I didn't even upsize my tires lol

 

Size and weight play a huge role in mpgs. I would try to keep the tire weight between 45-55 lbs to keep some comfortable driveability. Taller tires change your final drive ratio so if you go too tall you’ll be out of your power range also the truck will be working harder to turn them.

 

Since you are looking at the tire size that come stock on some TRD models, your gas mileage should be close to the same assuming you have the same gearing.

 

Well I went one size up and more aggressive tread, Cooper Discoverer AT3 and took about a 2 mpg hit at least.

 

These weigh 39lbs and are 32” (255/75/17)
NOT recommending this size as it does hit your mpgs, but if you were to do stock or 265/75/16 they would probably weigh similar or less! (Hankook Dynapro ATM) @slow TURD I4

 

It’s also depends if you choose an E rated tire which is a lot heavier than some other C rated options out there. In reality, tires can impact fuel mileage more than anything else. Of course, this compounds as you add weight and lift etc.

 

I traded my stock 245/75/16 for 265/75/16 (cooper adventurer H/T’s) and took exactly a 1 mpg hit.