Well guys just went through another tank of fuel with the new tires, 295/75R16 tires BFG A/T. <br><br>I'm seeing a signifigant loss in mileage from the stock Michelin's.<br><br>I'm getting 18.7MPG where as I used to average 19.7-20.3. Best mileage being 21.2MPG. All hand calculated and with the new tires I multiply the mileage by 1.037 to make up the size difference.<br><br>What are people getting with similar tires?<br><br>-CM

 

I run 305/70/16 and my trip meter is about .1 miles off. So I multiply the mileage on that by 10%. That gives me the correct mileage. You will see a decrease in mileage with the bigger tires cause it reduces your gearing (numerically). I you have a 4.10 rear end. With the new tires, you have something like a 3.73 (not exactly but you get the idea). What this means is that in town, your truck is having to work a little harder to accelerate than it did before. Not to mention the fact that the larger tires weigh more. But, your freeway mileage should have gone up. Since it numerically raised your gear (made it mechanically higer), you should be crusing at a lower RPM. Not much lower. Maybe 250 RPM or so. But every little bit helps.

 

blue-<br><br>first off, how did you figure @about just a 1/10th off? I have 4.10 gears, with stock tires 235/75 but get 18mpg. Too me 3.73 final ratio is perfect. being 4.10 is kind of low and 3.5 sucks the power. just my .10th

 

The 3.73 gear thing was just an example. I have no idea how much he is off. I agree, a 3.73 would be the perfect gear ratio (the 03's come with that) and I would love to have that. I have the 3.54 gears in my truck. I was told and have done the math with 10% thing. I can go by a mile marker and by the next one, my trip meter is only showing .9 miles instead of 1 mile.