What is really remarkable is some folks advocate using 80 psi in a wheel rated for 50 psi max because they have never saw a wheel with a split rim on rv.net.
With logic like that guess these same folks would say we can over load the axles because we don't see busted axles from over loading on rv.net.
I've had my share of split rim issues from over inflation caused by bad advice like some are pushing here and from wheels that didn't have a pressure rating and were though to be ok.
This from ; RVdoctor.com
A friend of mine had a travel trailer wheel split at the weld while traveling in Canada. When he got back in the States, he spoke with a man who said that the chrome wheels that come with the load range G tires cannot handle the sideway pressure exerted by the tires. He called me and told me about this since I have load range G tires on our Jayco coach with what appears to be aluminum wheels. Is there any validity to the claim about the weld? Phil E., (Sioux Falls, SD)
Phil, I posed your question to Walter Cannon, Executive Director of the RV Safety and Education Foundation, one of the foremost experts on tires and RV safety. Here's what he had to say:
"Having a weld brake although not common, does happen. Trailers are simply hard on tires and wheels. Whenever there are axles close together the lateral forces applied to the tires and wheels when turning are tremendous. This is particularly true when turning at low speeds like in campgrounds and in-town driving. Inflating trailer tires to the sidewall pressure will help them run cooler with less heat buildup as well as minimize the lateral forces applied in tight turn situations. These forces take their toll on the wheels and tires and failure will normally occur when the tire and wheel are at their highest temperature, i.e. running at highway speeds. Tires and wheels are matched to work together, in most cases this is based on air pressure ratings, if tires upgraded from an 80psi (load range E) to the 120psi (load range G) without upgrading wheels it could cause a problem. There is little one can do about the sideways forces other than to try to make as wide and smooth low speed turns as possible and avoid sharp tight turns. Aluminum wheels are normally milled from a solid block and do not experience the same type of problems as welded steel wheels."
and this from tireman9 blog on "wheels" from his rvtiresafety.com;
Bottom Line
You should never set the cold inflation at a level that is higher than the Max for either the tire OR THE WHEEL. Both the tire and wheel manufacturers take pressure increase due to operation heat into consideration so don’t bleed off hot air out.'
The internet is full of opinions from experts like these two.