I run 14.5 Mchelin XL's on my U-1300L Unimog. Weights are about 7000 lbs each axle for total of 14,000 lb. 35 PSI has proven to be the best pressure for most even tire wear, but also provides a nice ride. At 35 PSI we can venture offroad without airing down and still get good flotation.
I found pressure recommendations in a full range from 30-ish to 65 or higher. I drove one set of these tires for about 30k miles starting at 55 PSI and working downward in steps, doing pressure vs wear testing and measurements. Higher pressures definitely make the lugs wear irregularly, the centers wear first, and the ride is harsher, too.
IMHO the magic about Michelin tires is to let the movement/squirm take place in the sidewall, not at the road surface interface.
My wife and I just completed a 5000 mile camping trip out west in the Unimog with a "new" set of 14.5 xl's, and the wear was not bad at all. Much of the trip was at over 55 mph on hard surfaced roads. The fronts wear worse, so they have been rotated and are ready for another 5k.
(my wheels are one piece so tires are run tubeless.)
Bob
I've got Michelin XL 14.50-20's on stock rims and am wondering what air pressure would you guy's run.At about 35 lbs. they seem a bit rounded to me.Also will standard 9.00-20 tubes work as spares for the 14.50-20 tires?Thanks!
