After replying to a thread last week, I decided to take a look at my tire pressure. I had not checked it in months, so I figured it would be a little off. They were 45, 44.5, 44, and 42. I decided that I would bump them up a bit to see what kind of difference I would get in fuel mileage. I added air to them until they all had 50 lbs of pressure. It has been a week, and my fuel mileage has increased by about 1.5 MPG. These Toyo Open Country M/T's are E-rated and have a maximum pressure of 65 psi. Would there be any harm in going any higher than 50 psi, other than a harsher ride?

Oh yeah, I am getting about 14 MPG right now instead of the 12.5 MPG that I was getting.

 

1.5 Better MPG?
*goes out to the truck with the air hose in hand*

 

You may not see as much gain with the stock tires, as I suspect that they have less rolling resistance than these bi M/T tires. I can feel the difference though. The truck takes bumps harder and seems a little bouncier, but it also handles a little better.

 

You might get better gas mileage, but the tires will wear a lot quicker.

There are always costs associated everywhere..

 

That just means I will get that lift and 37's that much sooner!

 

The V10 mileage is 'tire pressure' sensitive.

My formula:

I will be out in the field (mud) with about 30 -35psi and have it back up to 55 - 60 when cruisin' the roads. Haven't really been in the sand yet, but I've heard of folks dropping it to 20psi and lower (definately not recommended for the road!)...

 

I may have to bump it up to 55 psi to see if it helps even more. I am sure that it will get to the point where the truck just takes bumps too hard.

 

Good deal, thanks for the info. I've had my M/T's at about 40 psi and wanted to bump them up to 50. I'll be doing this for sure. Thanks

 

Man, my stock tires are set at 65 psi. I also have the tire pressure monitor and it goes off when the psi is low.... Another thing...how the hell are you at 14 mpg's? I am still only at 11!!!!!!!!!!!!!!!!!!!!

 

No just the ride would suffer, I have an F-150 and bump my tires up to the sidewall max of 44 PSI when I am hooked to my travel trailer, keeps the sidewalls stiffer, less flexing = less heat in the tires thus more control and longer tire life.
Unloaded I run the pressure in the door jamb, 35 PSI.

 

If your stock tires are at 65 psi, I may just go up to 60 psi. What is the max psi on the stock tires?

I drive like an old lady. It's really hard this time of year because it takes the engine about 6 miles of driving to get heated up. My drive to work is about 20 miles. For the first 6 miles, I can see the MPG dropping, then once the engine heats up, it starts creeping back up.

If it makes you feel better, I filled up with Walmart diesel a couple days ago and now I am back down to about 13.5.

I want to tune the truck with the Superchips 1808 so bad, but I am holding off for at least six months. Once I tune it, the mileage should be over 14 MPG all the time.

 

This is old news to me and I posted the same here:
Best mod for increasing MPG??

Mileage results posted here:
https://www.f150online.com/forums/sh...7&postcount=21

Bumping up the fronts to 60 to 65 psi has yielded the largest increase in MPG. FWIW, my tires are the stock size, Firestone transforce HT (max pressure is 80 psi).

 

Ok, maybe I will bump them to 60 psi today and see what happens.

 

It's very interesting to find out what occurs from this. Keep it up.