Tire Sizes and MPG?

digitalamish · #1 11-03-2009, 04:26 PM

OK, so first off I bought a truck, yes I get it. I shouldn't be so picky. But I have to ask.

The stock truck comes with 17" tires. I am considering getting a set of winter tires on the stock rims, and then maybe moving up to a set of 18" or 20" rims for the summer. I am not looking to get knobby offroad tires (it's a 4x2, so why?), but a nice set of 3 season street tires.

My question is if moving up to a bigger set of rims will make an impact in the MPGs the truck gets? Or, as the ladies say, size doesn't matter?

Ignorant minds want to know.

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ChrisT · #2 11-03-2009, 05:13 PM

Well, you have to take in consideration of the total diameter of your tires\rims. Increasing those in anyway (larger rims or larger tires) is definitely going to decrease mpg's. For example, I have a 285\70\17 tire on my stock 17" wheels which is basically 33" diameter. If I were to put on a 16" rim and run 285\75\16 tires(also basically 33"), I'm not really changing the over all diameter of my wheels so my mpg shouldn't change that much if at all. If you do change your diameter by a good amount, your speedometer will be off and you will actually be traveling more miles then your odometer is reading thus making any gas mileage calculations incorrect\bad.

greencrew · #3 11-03-2009, 07:56 PM

If the overall weight of the wheel increases then your MPGs will decrease.
If the outside diameter of the wheel increases then your MPGs will decrease.

When you get bigger tires, both will increase at the same time.

05BlackFX4 · #4 11-03-2009, 09:34 PM

as long as your ratio stays close to your stock tires/wheels you will get close to the same MPG's..

The bigger the wheel you get the smaller the sidewall of a tire you will need in order to stay close to stock MPG...go too small though and you will find yourself blowing out tires and bending wheels when you hit bumps in the road.

snopro31 · #5 11-05-2009, 01:40 AM

on my 06 ive dropped around 2-3 mpg.

exact same size tires as stock 275 65 18 but I went with a all terrian tire that are softer then the stock rugged crapolas that came with it. however I expect my mpg to improve when it goes below freezing so the compound hardens up a bit

boyd220 · #6 11-05-2009, 10:14 PM

Hey snopro31 , Did you reprogram speeo when you changed tires. if you did not then milage is not off as much as you think.

snopro31 · #7 11-06-2009, 01:43 AM

Quote:

Originally Posted by boyd220

Hey snopro31 , Did you reprogram speeo when you changed tires. if you did not then milage is not off as much as you think.

I stayed with the same size. shouldnt have mattered.

Just a different tire.