Smaller tires & wheels = Better MPG?

So back when i got my 2007 5.7 4wd tundra, i was seeing average 14-16MPG, then i put on 275/70R18 Mickey Thompson A/T's and i've plumeted to 10-12MPG.

Besides my heavy right foot and a cold air intake that sounds SWEEET! Will installing some P265/60R18 cheap street tires help bring up my MPG?

Less rotating mass, less resistance with street tires, all that good stuff and saving milage on the off-road tires to be actually be used off-road... just brain storming!

 

No. Smaller tires increase torque, faster acceleration but won’t help fuel economy. That new tire size won’t affect economy as well. If you went from a LT tire with 6 ply sidewalls that only weighs 45 lbs and upgraded to an E rated tire that weighs up to 70-85 lbs then expect a drop in mileage. Rotating mass definitely affects mileage and slows acceleration which unless you drive like an ‘old man’ - see ‘Me’. I’m really aware of power on acceleration. If it’s city driving I watch the tach and keep it below 2500 rpm every time I accelerate. I just recorded 22 mpg with my 5.7 RCSB and I’m running Cooper AT3’s. They are a heavy E rated tire. Discipline will get you your mileage back.
Ya know and new air filter, maintenance etc
Maybe a slightly higher tire pressure. Instead of 30-32 psi try 34 psi. Don’t go crazy.

 

The weight of the tires is not that important, the diameter is the main issue

ive run p and e rated 275/65. Exact same mpg.

275/70 costs a few mpg

 

There’s a reason hot shot transporters use a stock sized tire

 

Even if you get a set of tires for dirt cheap and they actually help your mileage moderately, it is going to take a very long time to even break even to offset the cost of the tires and balancing.

If you pressure your tires up too much, they'll wear out faster in the center. Adjusting your driving habits is the only way to go because it costs nothing.

That's my logic anyway..

 

I disagree about tire height vs weight impact on performance. Taller tires do not necessarily hit MPG more than weight.

I was running 275/70-18 (33s) wildpeaks which are quite heavy. Switched to a much taller, but significantly lighter tires (5 lbs lighter) in 285/75-18 (35s) and my acceleration is better and MPG improved 1-1.5 MPG.

 

Shouldn't tire width also be a consideration? For instance wind resistance.

 

If the OP is worried about mpgs, he's driving the wrong vehicle. Sort of reminds me of the initial phase of the Smart car. People were buying it to save gas, it took 7 to 8 years to break even, and now you don't even see that POS on the road any more.

 

My company's garage actually has one...... lol

 

It's a "unicorn" now lol.

 

Well, consider the character that is currently driving that car, uh, mad unicorn sounds more accurate. But that's another debate all together.

 

Yeah i'm splitting hairs at this point, but we'll see, the tires alone are half the weight of my current, they're AT LEAST half the total weight of my previous. it'll take awhile to pay off 550$ in gas for sure

size correction 265/65 R17