I'm not going to get into a debate, and I'm not even going to post on this thread again. I'm tired of all the misinformation that gets repeated on here about never being able to go over 65mph with a trailer tire. I'm not going to debate if you should drive that fast, if you think you shouldn't, there's probably a good reason not to.
The simple fact is, the 65 mph max is for max load and max pressure.
on 08/12/2013 08:48 AM
Sent by: Goodyear Tire & Rubber Company Consumer Relations 728 1144 East
Market Street Akron, OH 44316 Voice #: 800.321.2136 Fax #:
Thank you for contacting our web site.
Special Trailer ("ST") Tires
Goodyear Marathon trailer tires
are widely used in a variety of towable
trailer applications and are designed and branded as "ST" (Special Trailer) tires
* Industry standards dictate that tires with the ST designation are speed rated at 65 MPH (104 km/h) under normal inflation and load conditions.
* Based on these industry standards, if tires with the ST designation are used at speeds between 66 and 75 mph (106 km/h and 121 km/h), it is necessary to increase the cold inflation pressure by 10 psi (69 kPa) above the recommended pressure for the rated maximum load.
-o Increasing the inflation pressure by 10 psi (69 kPa) does not provide any additional load carrying capacity.
-o Do not exceed the maximum pressure for the wheel.
-o If the maximum pressure for the wheel prohibits the increase of air pressure, then the maximum speed must be restricted to 65 mph (104 km/h).
-o The cold inflation pressure must not exceed 10 psi (69 kPa) beyond the inflation specified for the maximum load of the tire.
Important trailer tire care information and load / inflation tables are available on Goodyear's Recreational
Vehicle web site at www.goodyear.com/rv
Many trailer manufactures establish the recommended tire inflation pressure based on the 65 mph (104 km/h) rated speed for ST tires. In these cases, the ST tires should be inflated 10 psi (69 kPa) higher than the trailer placard for speeds up to 75 mph (121 km/h) (wheel must be rated for this higher inflation pressure). If the trailer manufacturer's placard specifically states that the cold inflation pressure is suitable for speeds above 65 mph (104 km/h), no additional inflation pressure adjustment is required.
Jennifer - Consumer Relations
Can Goodyear marathons be used at speeds over 65mph? Thanks, Jared
According to the Tire and Rim Association the inflation pressures and load specifications in general for any ST Radial trailer tires, regardless of the manufacturer, are designed and rated at 65 MPH. However, if the speed is higher than 65 MPH, the pressure and load need to be adjusted according to the following guidelines:
From 66 to 75 MPH - the tire inflation pressure needs to increase 10 PSI (not to exceed the maximum PSI the tire is rated for) but requires no load adjustment.
From 76 to 85 MPH - the tire inflation pressure needs to increase 10 PSI (not to exceed the maximum PSI the tire is rated for) and load should be reduced by 10%.
ST (Special Trailer) Radials are designed specifically for use on trailers. They have different construction features and materials that vary from Auto and/or Light
Truck tires. There are no merits in using a Light
Truck tire over an ST Radial if the intended use is for a trailer. Maxxis would not recommend any tire be used in any application it was not designed for.
Thanks for your inquiry and interest in Maxxis Tires.
The Maxxis Support Team
Moral of the story, contact your tire manufacturer for the REAL truth.