How many PSI do you run in YOUR tires?

[E.Roy]

Originally Posted by Old Mechanic

About 120,000 miles of tires at 45 PSI and not any uneven wear, on several different tires and cars-trucks running higher pressures for a decade. In fact based on my experience the tires will last longer, as well as the brakes and most other vehicle parts from hypermiling.

regards
Mech

I agree with you that the tires may last longer inflated 45-50, at least my experience backs that up in the 175/65-14 and 185/65-14 size at 50psi.

Snow tires (edit: Blizzak) are a different story. I have worn the center down on those at 35psi, they should probably be run about 30 for even wear.

[serialk11r]

Originally Posted by dirtydave

A little bumpy!

My lowered car is already super bumpy, so I run 36/40 or so on tires rated 50 or something like that for comfort. Coast down didn't improve much for me up from 32/36, though I feel like there is some improvement, but ride comfort got quite a bit worse. My car is only 2150lbs so I don't think rolling resistance is a big deal at any rate.

[Baltothewolf]

I run 44 (max sidewall) in my civic, that's cold though so they are probably at 50 when it's ~100F outside. My front left tire has a extremely small leak so it varies from 44-38.

[Miller88]

I'm still trying to see what pressure is best for fuel econ and treadwear on my newest set of tires for the focus, but I am doing 40/36 (f/r). For the winter tires on the Focus, I just do max on the sidewall. The winterfarce tires always wear the outsides nomatter what pressure is in them.

The Cherokee has 30-35 PSI depending on load.

[California98Civic]

Originally Posted by Miller88

I'm still trying to see what pressure is best for fuel econ and treadwear...

Apparently it might be useful to know something of the design of the tire's steel belts in order to know whether the center will life and wear unevenly when inflated above sidewall recommendations. It seems from everyone's stated experiences that not all tires are the same in this respect. So maybe design makes the difference...

[Frank Lee]

As a practical matter, there are no bias ply and belted car tires available anymore. But there must be detail differences in radial construction.

[CapriRacer]

Originally Posted by Frank Lee

As a practical matter, there are no bias ply and belted car tires available anymore. But there must be detail differences in radial construction.

Allow me to confirm that there are detail differences in the construction that affect the wear characteristics. That is why I have been arguing that you can't generalize that tires run at elevated pressures don't develop center wear. Some do.

[user removed]

The Kuhmos on the Fiesta just hit 30 k and have 3/8ths inch tread all across all the tires. When I can measure a difference in tread depth front to rear I rotate them but keep them on the same side. Based on the accumuulated wear, it looks like I can easily go another 30, maybe 45 if the wear is less when you have a cooler running higher mileage tire.

The car will be 4 years old in November, produced in November 2010. Those tires might last me until I'm 68 years old in 2018, the original tires on the car when new.

I never said anyone responding to this question is wrong, or dumb to run a pressure that wears the centers first. I can only speak from my experience and that is when you look at total cost of ownership, from a strictly accounting point of view and for me only. Tire wear is reduced 20-25% from running my tires at factory recommended pressure. Fuel mileage is up on top of the lower tire wear. Even if I was wearing out the center of the tire, assuming I was, the overall savings more than justifies the higher pressure.

Do what you think is best and enjoy the benefits of your actions.

I guess I'm either more cheap or lazy. With OE tires on basically new rims, after plugging one on the left side, I probably don't check the pressure more than monthly and it doesn't change much at all. When I rotate the tires, I clean the wheels and wax them. Have never needed to rebalance them.

Edit;
You seldon see me touching a brake pedal coming to an off ramp. The wife sometimes grabs on to something.


regards
Mech

[wdb]

Originally Posted by Old Mechanic

You seldon see me touching a brake pedal coming to an off ramp. The wife sometimes grabs on to something.

Not to drift* too far from the topic, but my wife misses our dear departed Fit most of all because it had a H---S--- handle right above the door, and the replacement vehicle does not.

Back on topic, I see references to Blizzaks and winter tires in general on this thread. It's important to note that Blizzaks in particular (and perhaps winter tires in general) have a few unusual features relative to all-season or summer-only tires:

• dramatically different tread block design, edge vs. center
• different rubber compounds at different tread depths
• two sets of wear bars; one to indicate when the tires are no longer fit for winter use, another to indicate total tire wear

* pun intended

[California98Civic]

Originally Posted by Frank Lee

As a practical matter, there are no bias ply and belted car tires available anymore. But there must be detail differences in radial construction.

Thanks. You're right, or at least I confirmed through the oracle (google). The bias ply tires in particular are completely out of the market, it would seem. And car too appear not to have bias belted tires, either. But bias belted tires appear to be installed on "some light trucks such as pickup trucks and SUVs," according to this site by an apparently 96 year old tire dealer claiming to manage the tire programs for 19 automakers' US market.

So, to the point of the thread: the relationship between PSI and changes in tread wear, if everyone's experience is true, would be about differences in radial tire design.