15 more PSI = 7% better MPG

[niky]

Helps if you have at least an instant economy gauge (if you don't have an aftermarket one)... you can see the economy level spike and stay high if you lift and re-press.

Been doing that with the CR-V without really thinking about it. Fiddling with getting the car into lean-burn while cruising.

[ECONORAM]

Originally Posted by cbaber

I plan on going to 55 or 60 after this current tank. I want to see the difference in fuel economy compared to how harsh the ride gets. I'm perfectly satisfied with the ride at 45 PSI. I can feel more bumps, but I am the type of person that likes to feel the road when I drive so it doesn't bother me a bit. And the girlfriend didn't notice, so that is always a good thing!

One more thing I should mention, lean burn is not working on my car, so there is further potential when I get that working again.

I was going to ask about the ride quality. I run my RAM's tires at 37-38 psi normally. Book says 35. Never thought of running max sidewall (44 psi). Tire wear still even?

Originally Posted by Joggernot

6-ply truck tires are rated at 80 psi. My father-in-law ran these on his truck and ran 80 psi all over the USA towing a 5th wheel.

Wish I'd thought of that before I bought new tires. Could have bought a higher load range...

[gone7]

Tire wear will not be even at higher pressure unless weight is added to press the tread surface flat once again. That is the actual factor involved.

More weight needs higher pressure in a given set of tires, but never enough to over-ride the maximum setting no matter what. The tire engineering takes into account the momentary increased load under a bounce condition or striking an object in the roadway, where the pressure will soar upward momentarily.

A tire designed for 80 psi will also expect a higher load. Without that load, the tire wear might become uneven.

It is far better to select a narrow tire width to increase mpg, IMHO, than to damage a wider tire by over-inflation. Trading mpg savings for an expensive tire replacement seems obviously counter-productive.

BTW, all tire pressure ratings are always assuming accurate measuring devices.

[rickc]

BE CAREFUL GUYS! i drove on the hwy on a hot day with slightly over inflated tires and one tire started shaking and wobbling like crazy - turned out it developed a "bulge" - lucky it did not blow out completely. anyways, destroyed tire and $100-$150 out for the learning experience....not worth it imho...

[Joggernot]

Originally Posted by ACEV

I wonder how it felt without the weight of that fifth wheel.

The truck was set up for towing. Ride was rock hard without the 5th wheel. With it, the ride was very nice.

[malibuguy]

I ran the tires in my old scion at 63-64 cold...rode like **** but gained the 3mpg I lost by switching to "fuel max" tires over stock

[cbaber]

Originally Posted by rickc

BE CAREFUL GUYS! i drove on the hwy on a hot day with slightly over inflated tires and one tire started shaking and wobbling like crazy - turned out it developed a "bulge" - lucky it did not blow out completely. anyways, destroyed tire and $100-$150 out for the learning experience....not worth it imho...

Were said tires properly balanced? What pressure were you running and what was the sidewall max?

[Aero]

Aren't you concerned the having such high pressure in your tires will cause premature wear of the middle tread?

[niky]

Depends on the car, depends on the tire.

On my R-Comp Advans, which are wide, sticky and have a treadwear rating of somewhere between "zero" and "negative infinity", running over 35 psi... yes... friggin' 35... will wear down the center blocks quickly unless you drove it like you stole it and exit each corner at 1g lateral.

-

On my truck and CR-V, we run 45 to 50 with absolutely no problem.

[MetroMPG]

Originally Posted by niky

Depends on the car, depends on the tire

Absolutely true.

Plenty of 1st generation Insight owners run their cars' Bridgestone RE92's at pressures *well, well above* what cbaber does... and still they generally wear the shoulder treads first... even on cars that spend the majority of their time on the highway.

It's not a given that pressure higher than placard = increased center wear. Depends on the car, depends on the tire. It hasn't happened to me on 3 different cars, 3 different tires.