mpg from 33x10.5 to 12.5 ?

So I have 33 10.5s on right now with the 3.4 motor and I'm getting like 15 to 16. Can anyone tell me about what I would be getting with 33 12.5s?

 

I get 14-15 city 18-19 hwy on 33-12.50s Hankook ATs

 

Everything else being equal, you can bet mpgs will suffer, at least a little. Anytime you increase the weight of the tire, and they will be heavier, you loose a little mpg.

 

I have 33x12.50s and am getting 18mpg overall with mixed driving. My tires are C load range, so about 10lbs lighter than a comperable tire in an E. I also drive gently; shifting at about 2k rpms.
Also, how are you mesuting your milage? Your odometer is off if you haven't adjusted it for 33" tires. Ive been using gps to clock miles, and theres about a 7% differnce in the odometer reading and the gps mileage.

 

My Yota has 285/75/16 according to what I found out they are 32.85 inches tall. Going 50mph according to speedometer and GPS shows 56mph but I haven't taken time to calculate what that would do for showing actual miles. So MPG is going to be off also if speed O is off also. I get about 220 to 230 on a full tank according to Odometer which should be off some. Hope that helps some.

Sittingbull2

 

You're adding weight and width, it will inevitably go down. I personally don't see a single reason whatsoever to run flotation width tires unless you DD on snow/mud/sand deeper than your doors . . .

 

With 33 x 12.50 BFG ATs on 15s with the 3.4L/manual I get around 14-16mpg.
While the mud/waterholes around here can be up to the doors in places, these tires have never let me down. The extra width is nice offroad in the snow, but on snowy roads...not so good. For snow tires I will eventually go thinner.

 

I used to commute 100 miles a day in a lifted 98 3.4/manual 4x4 with 33x12.50's and I got 16mpg on a commute that was all 55-75 mph. Gas was a lot cheaper back then though. Although they don't ride as good a 12.50 tire does add a bit of stability for cornering. Many people don't consider that as you go up in height you should really also go out in track width to maintain stability.

 

Thanks everyone. I'm going with the 12.5s.