Trailer tires
We have a dual axle travel trailer with 13" wheels. On our last trip blew one of tires. I started doing some research and found that these are ST rated tires which I think means they are rated to 65 M...
Forum Discussion
There's also this post, which says in part, quoting Maxxis...
"High Speed" is used to differentiate the M8008 ST Radial from other products we offer that are intended for industrial and/or commercial use, in slow speed applications. The Maxxis M8008 ST Radial carries a "Q" speed rating. However, according to the Tire and Rim Association, the U.S. tire industry specification authority, inflation pressures and load specifications in general for any ST Radial trailer tires without a service description, regardless of the manufacturer, are designed and rated at 65 MPH. ...Followed by the 10 psi / 10 %, etc. adjustments you gave. The discussion which follows ignores the "in general" qualifier. I read the response to be that the Maxxis M8008 is Q rated at full load, but ST tires which aren't specifically rated like the M8008 ("in general...without a service description") can follow those rules.
