17" TRD SEMA Wheels and 265/70/17 Falken Wildpeaks tires = decreased MPG

Has anybody put on 17" TRD SEMA Wheels with 265/70/17 falken wildpeaks and noticed the truck struggling a little, even with the OTT?

 

You put taller and most likely heavier wheels and tires on, so yes.

 

What do you mean by struggle?

I have aftermarket wheels and bigger tires on my trail edition and wouldn't say it "struggles" at all. Drives like it did with the stock wheels and tires with a hair more sluggishness but its barely noticeable. Goung up one size shouldn't make that much of a difference.

I deff did take a 1-2 mpg hit.

 

Yes. No vehicle likes larger/more aggressive tread pattern in comparison to stock size/street tire. You can compensate with tuning all day long, and the drivability may be improved, but the truck is still ultimately working a little harder to rotate the upgraded wheel/tire setup.

 

I guess struggles is a strong word. It just doesn't hold the gears (really sixth) quite as along as it used to. I am also at 7200 ft.

 

I would say that's normal then.

A tune can only do so much to help for the lack of low-end power these trucks have.

 

At 7100' up in elevation there is roughly a 21% loss in horsepower due to the 'lack of oxygen'. Adding weight, especially heavier wheels make it more noticeable.
I live at 7000. Use ECT and Smode when ascending. These V6 engines love to rev in the higher rpms, do not low rpm lug it!