Air Pressure on Tires?

I run 120 all around. 16 ply 11/24,5 and big weights...

Here's the web site...

http://www.michelintruck.com/tools/rolling-resistance-comparison/

 

I run max pressure in all my tires. Center wears sooner, but my tire costs are still around 3cpm vs 50cpm for fuel...


As for rolling resistance tables: http://americamovesbytruck.com/rollingresistance.php?sort=rrvalue&brandmfg=MICHELIN

XZA3+ 103
XDN2 140

 

I run the recommended pressures on the Michelin load rating charts. I run 105 on the steers, 95-100 on the drives (wide based). I got 220K out of my last steers (XZA3+), and they still had 8-10/32nd tread. I only changed them because I got $150 a tire casing credit and discount on the new ones. Basically a 2 for the price of 1 deal. My wide based (Xone XDN2 from the factory install) now have 348,000 on them, and they still have 14/32nd tread and wearing quite nicely.

The Michelin website has all kinds of info on RR for theirs and other brands of tires. Look under the Tools menu at the top of the page.

http://www.michelintruck.com

I just filled up on fuel yesterday for $2.09 a gallon. Any perceived savings that might be out there by running max pressures is really not an issue. And tires also are designed to take some of the shock out of road bumps and such. It has been shown that some suspensions take a real beating by running tires over inflated. So one "might" save little on fuel, just to have to replace suspension bushings and such sooner. I just see no appreciable benefit to doing the max pressure thing. Irregardless of the latest radio show banter or whatever. Tires serve many purposes. Stopping distance is negatively affected by over inflation. Sure, one should not follow too close, but it is that idiot who pulls out in front of me, unexpectedly, on a two lane road that really concerns me. I want my tires to be their best at everything they do, and the R&D folks who designed the tire have done all the leg work and know how to make tires perform their best. Chasing a tenth of a mile mpg as the only consideration for my tire inflation choice doesn't fit into that game plan.

But folks do goofy things to their cars, pickups, and big trucks all the time. Nothing will change except the names and the faces.

 

I was getting cupping on my drives and heal toe wear at 105 psi, I dropped the pressure to 85 psi and they are wearing good now. I haul 140,000 lbs super b's, traction is my main concern as I load in yards and fields and travel plenty of gravel. My trailer tires are at 80 psi so they float on the soft ground a little better.
Before you cry "under inflated" look at the load and pressure charts and you'll see that I actually could go down to 75 psi on the drives. Michelin XDS2 .
My trailer tires were wearing on the outer edges before, but they are leveling out nicely now too.

 

yeah on the tire pressure, what gets me is just the look of the tires when loaded at anything below 90. maybe I have been looking at over inflated tires too long. tires at 85-90 looks like a flat tire in the process.

 

Hi Cowpie, your post #4 makes about the best sense here. I never "pumped " my tires up either, and ran them at what you say. Running too much pressure always made the truck seem a little "squirrely", especially in rain or snow, not to mention what it does to the roads, if anyone cares about that. Like you say, R&D did their job, and I stuck to what was on the sidewall of the tire.

 

[QUOTE="semi" retired;4393523]Hi Cowpie, your post #4 makes about the best sense here. I never "pumped " my tires up either, and ran them at what you say. Running too much pressure always made the truck seem a little "squirrely", especially in rain or snow, not to mention what it does to the roads, if anyone cares about that. Like you say, R&D did their job, and I stuck to what was on the sidewall of the tire.[/QUOTE]
yeah but what is on the sidewall is max press , not ideal press. I always put max, cause I thought it was the recommended p.s.i. never new there was a calculations table until about 8 years ago.

 

I was thinking the same thing. But you have to remember if you want to run low pressure and haul somewhat heavy, when DOT comes up behind you or beside you he is looking at the tires flexing. Maybe your more likely get pulled over and scaled? They have pulled me over a couple times and excuse was your tires looked squatted.

 

I may get a copy of michelins p.s.i. calculations table & keep in truck to show my tires are NOT under inflated.