Forum Discussion

Teeshot1939's avatar
Teeshot1939
Explorer
Jun 20, 2020

Tire Load Rating Questions

2 years ago the truck tire shop installed 8 new Michelins (275/80R 22.5) on my tag axle diesel pusher that were a G rating. I now realize that the RV labels states it should have H rating tires. What is the difference in G and H. Weight allowed? Number of plys? Both or something else? Should I immediately switch out the tires to an H rated tire? What are the possible consequences if I don't? Thanks.
  • Ply ratings and letter rating really don't matter that much. The tire sidewall will always have a maximum load rating. THAT is what is important.
  • Look on the side of the tire...it gives the load rating as weight.

    H will generally be higher than G but it's an old style rating from back when they made stronger tires by adding more plys...Now it's done by modifying the steel belt configurations.

    As others have said, take it to the scale (loaded for travel) and see where you fall. If you are under the rating for the current tires, no worries. Deal with it next time you need fresh tires.
  • Be aware that many tires with higher load ratings (like many going from G to H) have higher load carrying capacity AT HIGHER PSI's.

    In some cases, those PSI's are above the rating for the OE wheels. So, verify mad wheel PSI before assuming you can carry the PSI to give you those higher load carrying capacities.
  • I changed from 10x20" to 1100 x 22.5" on Quicksilver. Load range H

    I had first thought having a major increase in tire size and rating for all 10 tires would make a joke out of weight capacity.

    Until I took the loaded-for-bear rig to a public scales.

    You need to first load your rig including water, fuel, and all the junk RVers take along on a long trip.

    Only then will reality rear its ugly head. And make buying new tires less unpalatable. Also weigh the front axle separately. I weighed my tagger separately.
  • The "G" in your size mentioned will carry a specific weight in single or dual application at MAX inflation. Same goes for the "H" tire but it will carry more.

    I highly advise weighing your rig and making sure the tires meet your weights.

    Look up "Tire weight/inflation chart" for your tire size and load range.
  • X2, fj. Start with the tire manufacturer. Do you know your axle weights loaded and set?
  • Have you tried doing a Google search for your question? You're likely to get solid information rather than opinions and wrong information on a forum. For what you're searching, I would trust a tire site's specs before I would trust a forums' members' information.

About Technical Issues

Having RV issues? Connect with others who have been in your shoes.24,190 PostsLatest Activity: Jan 24, 2025