Trailer tires take all the abuse of trailering and usually don't get the attention they deserve. Most are not aware that tires have a DOT 7 year shelf life. This is due to the material breaking down over time. Trailer tires are normally stamped ST, or Special Trailer, tires are intended only for trailers. Your average passenger car (P) or light truck (LT) tire is a radial design. These tires are designed for different purposes than trailer tires.
Posted by on 12/8/2021
to Service Recomendations
Several things to look for when inspecting your tires:
PSI Rating - Trailer tires should be run at what is stamped on the tire sidewall. All to often we see owners inflate their tires to 30-35 PSI because that is what their car usually require. Trailers handle more capacity load per tire than cars do and when not running them at the recommended PSI it causes the tires to prematurely breakdown the sidewalls due to the heat built up in trailer applications. Typical trailer tires are rated for 50 to 80 PSI.
Date Code - This information is helpful in identifying when you should be planning on getting replacements. Every tire has a date code stamped on the sidewall, which is the date the tire was manufactured. The date code is usually at the end of the DOT I.D. and is a 4 digit number. The first two numbers indicate the week (out of 52) and the last two digits indicate the year. Example would be 3220 which identifies the tire is made the 32nd week of 2020.
Weather Cracks - Check the tires for cracks or separation which is caused by age and exposure to the elements. Usually weather checking (cracks) are found on either the inner or outer sidewalls or both. Separations are harder to identify as they are more commonly seen in the tread area. most of the time separations are seem light humps or bulges.
Tread Wear -
- Normal tread wear: Normal tread wear is easy enough to spot by looking at the tread wear indicator on your trailer tires. The indicator is a straight line that reaches from the edge of the tread to the edge of the opposite side of the tread and once it’s even with the tread itself, it’s time to replace your tires before they become a hazard.
- Wear due to over-inflation: If you’re a little overzealous when it comes to the PSI in your trailer tires, you’re bound to see signs of wear associated with over-inflation. Overinflated tires will experience wear through the center of the tread so that it appears to have a smooth strip down the center. An easy way to correct over-inflation wear is to let some air out of your tires.
- Wear due to under-inflation: If you’re lacking in tire pressure on your trailer tires, it’s going to show via wear on the inside and outside edges of the tire. The center of your tire tread will remain in good condition, but will be marred on both sides by wear that can easily be corrected with a little extra PSI, to bring your tires back up to their ideal pressure level.
- Camber wear: Another type of wear that affects half of your tread, camber wear can be the result of an impact issue or an overloading situation. Camber wear makes your tire look slanted. This is normally a sign that the axle needs to be replaced.
- Spotty wear: The cause of spotty wear is tricky to diagnose, but generally, it falls under the realm of stoppage and terrain. Wheel lockups, skidding, out-of-balance tires or uneven road conditions can cause spotty wear—avoiding sudden stops, being easy on the brakes and balancing your tires can work to slow the progress of spotty wear.
- Non uniform tire wear: If your seeing tire balding on one but the others are fine usually is an indication the axle needs to be replaced. This can be caused by bearing failures, impacts, curbing, overloading.
Inspection of tires is included in our yearly service inspection. Call our service department today to see about getting your trailer in for its yearly checkup. 253-922-0771