To Sway or not to Sway...

[Byron Kinnaman]

Originally Posted by Paul O.

I would like to see somebody knowledgeable about tires tell us about the maximum speed rating. I suspect that it has little to do with the critical speed of the tow vehicle with trailer system, and more to do with the construction, heat generation and resulting potential for overheating. But even so, the 65mph max. towing speed is still a good rule of thumb.

It used to be molded into the sidewall of TT tires. I haven't checked my new tires and haven't heard of it changing.

[Mike_L]

This information is available from the tire manufacturer and usually stamped on the sidewall of the tire. I tow a tandem axle trailer. When I buy new tires I ensure the combined maximum load rating of all four tires is at least twice the maximum loaded weight of my trailer. Over heating is the main cause of tire failure on a trailer. Tire flexing is a major cause of tire heating. Keeping the load below half the tire rating minimizes heating. Maintaining proper air pressure also minimizes flexing and heating and increases stability of the trailer, especially at highway speeds.
This also applies for the tow vehicle. I use 10 ply tires on a 3/4 ton diesel. They cost twice as much to buy but last three times as long as the lighter duty tires plus they are much more reliable and stable.