The blow out trip

When considering the screw holes, bear in mind that the only part of the wall that offers screw withdrawal resistance is the thin skin of the wall interacting with the thread of the screw.  The styrofoam behind the skin doesn't do much.  Either filling the hole with epoxy or going to a slightly larger screw will do pretty much the same thing.  As for gluing the fenders on, with a very strong adhesive, it's not likely that any adhesive or adhesive tape is strong enough to resist the impact force of a failing tire.  But, peeling off the adhesive from the gelcoat may not be very good for it.  You may have some extensive fiberglass repairs that are much more complicated than simply putting in new screws, filling, or drilling.  Maybe having "break away" fenders may cause less costly repairs than pulling off a big chunk of fiberglass or gelcoat.  

I don’t agree. I would attach the fenders as well as possible, using good adhesive and using fresh screw holes. Why plan on having the fenders come off and why try to reuse damaged holes? I also don’t buy the “China bomb” theory. I place the fault on FR for mounting marginally rated tires on their trailers. Get ST tires, load range d, and keep them properly inflated. If you like, buy American, of course that’s fine. I’m personally running Chinese 15 inch LRD’s with 2500 lb ratings. my $0.02.

Tomtreas, I suggest when you put the new screws in, use a bedding compound caulk in the screw holes.  It seals them and helps bond the screw to the sides of the hole a little.  On my boat I used 3M 5200, but there are plenty of similar bedding caulks on the market.

If I remember correctly from the days I defended some tire manufacturers, on a radial tire, the tread separation you see in the photo is the "normal" mode of failure.  As the tire fails, air enters the space between the tread and the plies of rubber coated fabric to which it is bonded. It is not uncommon for the tire to sustain damage unknown to the user which eventually allows air to seep into the body of the tire.  Some times, the quality of manufacturing results in incomplete bonding of the tread and with heat, it creates an increasingly big separation of the tread until failure occurs.

Originally posted by mjlrpod   BTW any chance you can share brand that blew out. It would be good if we can keep track of brands that are known to fail.