Tire pressure

I just had Michelin LTX/ATs P235/75R15 put on as replacements for my 1998 Merc. Mountaineer. I had them installed at Sam's club. The guy there recommended 35 psi. A few days later I went to have the oil changed at the Ford service station. Without asking, they pumped the PSI up to 40. I already know which pressure will have the better ride. But will 40 cause some excessive or uneven wear? Thanks for any input.

 

[jimbo74]

40 is too much...
being a retired tire guy:

put 35 for economy and 32 for best ride....

 

[Jim F]

I agree. 35psi is the max pressure rating for the 105S tire. This pressure is where the max load rating is rated. If you are hauling or towing a heavy load, 35psi would be recommended. I run 32psi and am happy with the ride.

I hauled a load of firewood both in the back of my Explorer and in a small utility trailer. At 32psi the tires showed no sign of squat. They didn't appear to even see the load on them. In fact the rear (ground to rear wheel fender) of my Explorer came up almost 2 inches after I unloaded the firewood from the back. The before and after measurement was after the trailer was unhitched, so the 2 in change was just the wood in the rear cargo area. I was pulling in late afternoon and in one area the outside temp got to 100 degree. It was about a 200 mile trip home loaded (with wood that is). One stop for a late lunch. When I got home all 4 truck tires were the same temp to touch. Before with the Firestones, the rear tires usually were hotter than the front and this was without a load.

Needless to say, I love my Michelin LTX A/T's and 32psi would be my recommendation for all-round use except for that extreme occasion.

 

[Steven68504]

Thanks for the quick replies. I'm off to buy a tire pressure guage.