Tire pressure

Thanks. Yes, original 15 inch rim: it says "max load ...lbs E". I can't read the exact lbs but since it's original, the Casita trailer didn't suddenly get heavier.

Casita originally has load range C so E being able to carry more weight, I thought it would be ok. Not sure why having one tire with the ability to carry more weight is an issue? Does someone know?

P.S. Both tires are 5 ply.

This thread made me think about what's unsafe IF both tires are the same size and set to the mfg recommended tire pressure based on axle weight. And given that's it's neither a steer or drive axle.

What I come up with is a potential stability and braking especially in an emergency situation.

But whatever the real situation might be I default to liability not wanting to explain how my mismatched tires were not a problem.

Trailer tires should be inflated to the max tire pressure listed on the tire. You shouldn't use mixed load rated tires. Is the new tire on the old rim? If so what is the pressure rating of the rim? It should be stamped on the rim somewhere. If it will handle the pressure for the new tire, get a new matching tire for the other side.

Sounds like a big no-no to me. You are supposed to have the same tire on each end of an axle. It is ok to have different tires on the other axle as long as they are the same at each end of that axle.

The C might be a trailer tire and the E a truck tire from the OP. You pick the psi of the truck tire from the weight it is carrying, while the trailer tire is usually at its max regardless of weight (from what I have gathered about all this)

IMO you have an unsafe situation there. Better to get a second new tire and maybe have the older C as a spare. If you do end up with the C on there after a flat, drive slowly to the garage and then put it back as the spare.

I would use the tire pressure, and load range tire stated on the driver's side front of trailer placard. I would not use tires that are mismatched, as to plies, load range, or physical size, when towing any trailer at speed, even a light wt Casita.

Jerry

An “older” tire on a single axle trailer is asking for trouble. Replace them both. Load range D is probably sufficient. Usually 65psi. Use the Hi-Run as a spare for very limited miles.