Need Advice - Bad Gas Mileage After Tire/Wheel Upgrade

A couple weeks ago I went from the stock Toyota wheels/tires 265/65/17 to Nitto Terra Grapplers and XD Hoss 285/60/18. My gas mileage has decreased tremendously. A full tank used to average 310-320 miles driving a steady 80 mph. Now I'm lucky if I get 260 miles to a full tank driving at 70 mph.

I love the look and handling of the new wheels, but I need to know if there is anything I can do to bump up my gas mileage again? Other than going back to stock.

 

no such thing as free lunch..that is a pretty big drop..

drive even slower?

 

The wider tire causes more drag...more air resistance and rolling resistance. Just plain ol' physics.

About the only thing you could do is mess with the air pressure...try adding a few PSI.

 

Yes it drives slower and does drag. So the guy at 4 Wheel Parts telling me I need to replace my rack and pinion is wrong I'm assuming.

 

How the fuck will the steering rack affect mpg? It turns the wheels it doesn't move the truck. I ran those same size tires with 4cyl 5 spd AC Prerunner 4x2 and was gettin 20 mpg all the time. Went with 275/65/18s this time and I can feel the difference it makes. 285/60/18 = 31.5x11.5 275/65/18 = 32x11. Now I'm pullin 18 mpg. All you can do is drive less than 80 or go back to stock. Also consider that the bigger OD will slow your speedo/odometer where it = less miles per tank but if you add the difference back to the tank mileage that your speedo is off, it'll really be more mpg than you think. Check speedo with a GPS on the hwy to see how much it's off.

 

It happens all the time, when you go with a lifted truck and bigger wheels your MPG goes down...

It is what it is...

 

I'm running stock size tires and my mileage tanks running 80 vs running 70 mph. I'm guessing the bigger tires are just magnifying the affect.