Tire issue

What brand of tire?

Tire cupping

Are you referring to cupping on the actual sidewall of the tire? Or cupping on the tread area of the tire? Got a photo or two?

Could be out of balance. Being out of balance can cause one tire to wear differently than the others. How do I know? It's happened to us.

I agree with out of balance.

for the ones that asked it is a Goodyear G-114. and it is cupping on the tread. ( not side wall)

Do what 2oldman said.

I would spin check all tires. Even if the tire checks correct (!) replace it.

Take it to the dealer, it doesn't sound good, and it's unlikely to heal itself. :) Might as well get it replaced before it totally goes south on you.

I agree it is probably out of balance, but might check the brake and make sure you don't have a sticking brake or sketchy bearing.

Thanks everyone.

If after a spin test, checking for out of balance condition, and replacement - if it happens again, check if your rig is out of alignment. We had that condition for two years in a row. Our RV tech recommended a local shop to check alignment after replacing the hangars, U bolts, and replacing the Equa Flex suspension parts; he was right. We were out by 1/4" and that's a lot. The alignment check was about $250 but well worth it.

Every year we take our FW to the tire shop and have them to a spin test and inspect all the tires. So far so good after new tires in 2014 and fixing the above issues.