Any input much appreciated regarding use of MPT81 335/80R20 in a 4x4 camper in the 19-20k lbs GVWR:
I have been looking at the MPT81 for a couple of years now and getting close to pulling the trigger on a set with hutchinson wheel. I've gotten some great info from various owners but one alternative that seems to be popping up is the Goodyear MSA G275, which [i think] is the standard issue on the GXV Adv Trucks. The two tires actually seem to be similar load/pressure-wise. The G275 is a lot more expensive but maybe it will last longer.
Comparing these tires, the ply rating vs load/inflation is confusing. If my conversions are correct and charts I'm looking at are up to date, it looks like this:
G275 12-ply max 6395lbs @ 80PSI, 6100lbs @ 75PSI, max speed 81mph
MPT81 22-ply max 6779lbs @ 94PSI, 5974lbs @ 76PSI, max speed 68 mph
Ply rating seems erroneous or irrelevant but I could be wrong and wonder if the sidewall on the G275 would be prone to overheating? On the charts I would imagine similar (safe) load capability running either tire at 80PSI but the G275 despite lower ply rating somehow better at a lower operating pressure and apparently has the ability to travel at higher speeds, is this possible? I am inclined to believe that GY, in selling these to USDOD, has a lot of miles of use on these tires and that the low ply rating doesn't mean they're not ready for abuse.
I am on snow and ice a good portion of the year and the reports of MPT81 being sketchy on ice are a concern. My hwy/dirt road driving time percentage is about 70/30%. I am on snow/ice 6-months out of the year and do as much winter travel/camping to ski and climb as i have time for. I dont need to go fast, 65-70mph is plenty. I am primarily concerned about load capability not being maxed out, performance on long stretches of dirt, washboard road and handling ice and snow. Anyone out there feel strongly that one tire is preferable to the other for any reasons mentioned above. Again, thanks for info as I research these tires.