Simple question guys, What is the optimum tire pressure for fuel mileage unloaded for my size truck? (everything is stock) Thanks for all the great info, I've learned loads.

 

If all you care about is fuel mileage then run your pressure up to the max listed on the sidewall of the tire.

However, that will potentially cause uneven wear (center will bald first). It will also give a bumpier ride and give slightly less traction due to a smaller footprint.

Those drawbacks aside, I've been meaning to run my pressure up higher also. My mileage is deplorable and it's a truck so I don't give a rats about the ride.

 

If you run at full rated pressure the tires will wear unevenly and a bumpy ride will actually reduce milage the door sticker will give you proper inflation 60 front 70 rear I think . from the factory mine were at 40 I raised them to the door sticker numbers and milage is very good 21 plus mpg on my 600.

 

Check the old handy-dandy owner's manual. There's a tire supplement that has suggested inflation pressures based on "light" or "heavy" loaded trucks. I usually run mine about 2 or 3 psi above the "light" load psi recommendations and has worked out great for me.
Greg

 

Thanks for the info. This web site is great!! We as diezel owners should form our own mini union for the few of us with problems that the dealership won't acknowledge or fix.

my 2 cents

 

Yes, go with the pressures in the owner's manual supplement. I've never had a vehicle where the door sticker had the correct numbers.

 

Owner's manual. For the Michelin LTX A/S in adition to varying pressure according to load, when driving over 65 mph one needs to add 10 psi. Looking at just tire pressure one is maxed out with 80 psi with a maximum load, so one shouldn't drive over 65 mph with a maximum load as an additional 10 psi can't be added.

 

Is that only correct if you have factory tires, what if you have something like bfg 315's?