Tires: Old trailer tire conversion, passenger car tire, tire molds

Question
Hi Barry

I was searching on line for information to replace my old trailer tires.  8.55-15ST. They have a 2000 lb load rating.  I did not see anything on the tire indicating they are tubed or tubeless. I came across someone with the same situation on your web site and you indicated the problem was the old rims  that use those tires (tubed) are not designed to hold air.  Can you suggest to me what modern day size of tire could replace the 8.55-15ST on the same rim and then I would use the old tubes or get new tubes in the new tires?  If that would work that would seem easier than replacing tires, rims and axles.

Thank you

Answer
Scott,

You have to be careful here.  8.55-15 was an old passenger car tire size and those were tubetype.

But when those molds became obsolete, the used them to create tires for trailers - and those are tubeless.  But that happened to a lot of tire molds.

One of the more common trailers sizing systems is similar to our current system - and the tire that most closely matches yours is the ST225/75R15.  It's a little wider, but can carrying the same load - your are looking for at least a Load Range C.