Check out my last post here:
Trailer tire confusion
I replaced my OEM Carlisle load range C tires after a blowout 1 year after I bought the camper. The tire tech showed me severe inter tread and sidewall cracking that meant the ST tires were improperly made. Carlisle offered to replace them (discounted for use) PROVIDED I shipped all 4 back at my expense and it turned out they were as bad as the tire guy stated. NONE of the damage to the camper would be covered by them.
Will I did not because I was so mad I could spit nails at that point.
They went to the recycling yard.
Upgraded to Marathon D rated tires and never looked back. My steel rims are rated to 60 PSI (not quite OK at the max sidewall pressure of the D rated tires, but since my camper is not overloaded and I run the tire pressure at 58 PSI cold - based on 10PSI over actual load rating for max trailer speed increase - Goodyear website), I feel safe and my tires don't make my trailer bounce.
Lou and Laura with Bella - German Short Hair Pointer
2008 GMC Sierra 2500HD Crewcab SB Allison Duramax
2010 Flagstaff 8526RLWS - Superglide 3300
HAM CALLSIGN - KC3FFW