Trailer tires when to replace them

The average life of a trailer tire is five to seven years. Most trailers spend a lot of their time sitting still. So your tires will probably need to be replaced before the tread wears out. Maybe it's cracks from the sun or maybe it's from sitting too long underinflated. When you have had your tires for about five years, it's time to think about replacing them or having a professional check them. It's also important with the kind of weight and load that your trailer puts on them to have them checked on a regular basis. You can also tell how old your tires are by the date code on the side wall of the tire. It’s only on one side so it may be on the side facing the trailer. You may have to get under the trailer and look or take the tire off to see the date code. The manufacture is required by law to put it on every tire, but it doesn’t spell it right out. The date code starts out with DOT with some other letters and ends with 3 or 4-digit number. The first two numbers are the week that it was built. Being there are 52 weeks in a year that is the max. The last one or two numbers tell you the year. So for example the last four digits are 1010 that means that tire was built on 10th week of 2010.


How to decide what tires you need.

We recommend sticking with the same size you have on your trailer now. To check for the size, it is on the side wall of the tire. Trailer tires will start with the size for an example ST205/75R15. The ST stands for special trailer. The numbers are the size for example the 205 is the width of the tire in millimeters. The 75 is the ratio of width to section height. Then the letter could be a R or a D. The R means the tire is a radial tire. That means the ply cords run in a radial direction. The plies run parallel to each other and vertical to the tire bead. Stabilizer belts are applied over the plies to give extra strength parallel to beads. The D means that the tire is a bias ply. A bias ply tire has diagonal or bias ply’s. These plies crisscross making the tire strong because the plies overlap each other. What is the advantage going with a radial tire over a bias ply tire? A radial tire is steel belted, has lower rolling resistance, has a smoother ride and good at high speeds. A bias ply tire has rubberized nylon or polyester mesh belts, has higher rolling resistance, has a harder ride and runs hotter than a radial. The last set of numbers are the rim size for example ST205/75R15, the 15 is a 15-inch rim. The next thing to look for is the load range. Try to stick with what the axle is able to carry. The load range is a letter on the side wall of the tire, it can range from A to E. Load range A is a 2 ply tire, B is a 4 ply, C is a 6 ply, D is a 8 ply and E is a 10 ply tire. You want to make sure to get the right load range for your trailer.

Here at Tri County Wheel & Rim we carry a selection of tires, different brands, sizes and load range. If you have any questions feel free to email or get ahold of us through our web site,