Comparing Special Trailer Tires in Size ST205/75-14 with Differing Load Range Ratings

Question:

Which is better trailer tire 205 75D 14 or 205 75C 14?

Expert Reply:

The only actual differences between two special trailer tires in the same size but with different weight load range letter codes, C and D in this case, are their weight carrying limits in pounds and their required inflation pressures in psi. For reference, the linked page displays all of our special trailer (ST type) tires in size ST205/75-14.

These tire options include items with either radial or bias ply construction and tires in either Load Range B, C or D. As examples, Kenda tire # AM1ST84 is rated as Load Range B, meaning good to 1430-lbs at its specified 35-psi pressure; Kenda # AM10234 is a Load Range C, meaning good to 1,925-lbs at its 60-psi inflation pressure; finally the Load Range D tire # AM10235 is good to 2200-lbs at its rated 75-psi pressure.

The benefit of using tires that can handle more weight than you're actually putting on them is that they will tend to run cooler. Tires used near their limits naturally tend to run hotter, and this heat is the root cause for much trailer tire failure. By selecting tires that offer a good safety margin in their weight rating you build in some insurance, so to speak.

The other main causes for undesirable heat build-up in a tire are incorrect inflation pressure (either too low or too high) and operating the tire at speeds higher than that for which it is rated. Some special trailer tires, such as D-rated # AM10235, are rated for highway speeds up to 81-mph. If you routinely drive at 70 to 75-mph on the interstate then you really want to use tires rated for higher speed. If we do not specifically call out a speed rating in a tire's specs then that means its speed rating defaults to 65-mph. Of course it is never a good idea to run tires at higher speeds than what they are intended to handle.

Any brand, type or rating of special trailer tire will last longer if you always observe rated weight, pressure and speed.

expert reply by:
Adam R

Ask The Experts a Question >>


Products Referenced in This Question




Product Page this Question was Asked From