The Toyhauler I just bought has tires made in 2000, so they will only be used from my house to the tire store.

It has 16" LT's on it now, I forget the brand. I also need to decide what to put on...

 

I've been towing travel trailers since 1970 and feel I've learned a lot over the years, some the hard way. Quick response: (1) US manufacturers seem to put the minimum axle capability on trailers which causes axle twisting and bending when you finally load everything in it that you want to carry. Most of us overload them; (2) Second, they also put tires on them that will barely carry the trailer's enpty weight so they seem to blow out due to overloading and/or overheating.
I started several years ago putting tires that had a higher load rate (8 or 10ply rating). Tires carry load well, do not overheat when aired to recommended pressure, and rarely have a blow out. Doesn't prevent punctures from nails, glass, etc., but doesn't blow out when you hit a chuck hole. I feel a lot better traveling without so much worry.