I can only tell you about the Goodyear Marathon tires our TT came with.
We custom ordered our trailer, brand spanking new from the factory. It weighed 3995 lbs., and had dual axles. 4 tires sharing the weight. The tires were properly inflated, the trailer was level because of the weight distributing hitch, and I kept the speed under 65 MPH, which is the limit for ST rated tires.
This is one of several blow outs. The tires were less than 5 years old, not sun rotted, not underinflated, not overloaded.
These tires are ****, period. You can spend hours on Google reading the other horror stories.
Three things happened after this last experience. I started carrying two spare tires, all Goodyear tires were replaced with Maxxis tires, and I started using a TPMS.
Zero problems since. FWIW, replacing a tire on the side of a hwy sucks!
If you have this brand/model, I'd highly recommend replacing them ASAP. Nothing you can do to improve the situation, short of replacing them. When is a convenient time for one to have a blow-out?... because Murphy says "nah, I have another plan!".
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