Just changed from Pirelli Scorpions to Michelin LTX M/S2's and not sure of correct tire pressure. Anybody running these?
On the Pirellis I was using 40lbs most of the time and 44lbs with a heavy load and towing.
Same for Michelins?
Tire pressure is a function of load to be carried and the tire size, of course limited to the maximums of the particular load range. Brand has nothing to do with it; if the tire size is the same then the pressures would also be the same.
I run the same tire at 40PSI. My truck is a fair bit heavier than stock, with a replacement front end, commercial topper, and several hundred pounds of equipment on board. They seem to wear fairly evenly (I'm on set #3 at 138K).
I always run my P rated tires at 38, this seems to be the sweet spot for even wear and gives a few pounds adjustment for temperature changes. I read years ago, this may have changed by now, that P rated tires reach their full load carrying potential at 35 PSI, the rest of the adjustment up to 44 PSI is for sidewall flex.....the footprint, if you will.
Edited to add: Originally I heard the above information when I emailed Nitto about the max pressure being 35 PSI on my new Terra Grapplers that I had installed on my old Dodge truck. I was concerned because any other passenger rated tire I owned to that point had a max inflation pressure of 44 PSI. Their reply in a nutshell, was that a P rated tires max load potential was reached at 35 PSI and the rest other 9 PSI was just foo foo (not verbatim obviously). A quick Google search lead me to Tire Racks tire tech page that basically confirmed this: