Dot dating tires


Maintain air pressure at the maximum PSI recommended on the tire sidewall.It's best to check tire pressure with a quality tire gauge when tires are cold and in the shade.Under inflation is the number one cause of trailer tire failure. The first two numbers indicate the week (out of 52) and the last two digits indicate the year.An underinflated tire creates abnormal tire flexing and excessive heat causing: - Ride and handling problems - Decreased fuel efficiency - Reduction of tire life Driving on tires with too much air is also not recommended. For example, 3409 means the tire was manufactured the 34th week of 2009.Over-inflated tires are more likely to cut, puncture or fail by sudden impact. Every tire has a date code stamped on the sidewall, which is the date the tire was manufactured. Please keep in mind that remaining tread is not an indicator of tire life as the irregular duty cycle requires that trailer tires sit in extended storage under static load conditions often for long periods without movement or maintenance causing the tire carcass (internal structure) to break down, a condition undetected by visual inspection. Trailer tires are designated “ST” for “Special Trailer” tires.Trailer tire requirements differ greatly from automotive or light truck tires.Automotive tires are designated “P” for Passenger or “LT” for Light Truck and are not designed for trailer use.



The construction, design, materials and testing used in “ST” tires meet the higher load requirements, duty cycles and special demands of trailering. In the past, most trailer tires were rated at 62 or 65 mph.Today, some of our tires are "rated" (speed symbols) at 87 mph (N), some at 75 mph (L), some at 65 mph (J: ST tires) and some at 62 mph (J: non-metric tires).Please remember that speed ratings are test speeds and not recommended driving speeds.The ratings apply only to the tire itself, and not a particular vehicle.

The speed rating does not mean that the vehicle can be safely operated at the tire's rated speed.

Is it a good idea to install tubes in trailer tires?