Replacing Existing 215/75-15 Tires on Homemade Trailer with 205/75-15 Size Tires

Question:

I have a homemade trailer that is made with 2inch thick-walled metal tubing. The current tires are P215 75R 15. Will a 205 75R 15 be a viable replacement? The current tires are weather checked and dont hold air for more than two weeks. I really only need to move the trailer 70 miles where it will become strictly off-road for moving cord wood.

asked by: Jim K

Expert Reply:

Your current tires are for a passenger car, so switching to trailer tires is definitely recommended.

You can certainly switch to the 205/75R-15 tire size. This size would be about 3/4 inch smaller in diameter and have a tread width about 1/2 of an inch narrower than what you're using now.

If you'll be using the trailer primarily off-road, I'd recommend using a bias ply tire. Bias ply tires have a stiffer sidewall, which will work better for off-road use. They're also a bit less expensive.

You don't mention the weight of the trailer or how heavily it's typically loaded. You'll want to choose tires with a combined weight rating equal to or greater than the weight of the trailer plus its load. For example, the Taskmaster # TTWSF20515C is a 205/75-15 bias ply tire that's a load range C. It has a capacity of 1820 lbs when correctly inflated to its maximum pressure of 50 psi. Assuming that your trailer is a single axle, you'd have a total tire capacity of 3640 lbs.

I've linked you to a helpful FAQ article about trailer tires.

expert reply by: Mike L