Is a ST205 75D15 a radial?
This size tire is available as a ST205/75-D15 or as a ST205/75-R15. The D indicates that the tire is a diagonal bias ply construction and the R indicates that the tire is a radial tire construction. Beyond the size and type, there are load ranges for tires. Most trailer tires are load range B, C or D.
What is the difference between 205 75R15 and 205 75D15?
The D in 205/75D15 represents that the tire has a bias ply construction whereas the R in 205/75R15 represents that the tire has a radial ply construction. The difference between a bias and radial ply is in regards to the directions of the cords.
Can you use radial tires on a trailer?
Yes, you can use radial tires on a trailer as long as they are trailer tires. Trailer tires will have ST in front of the size. Radial indicates which way the belts run in the tire.
What does the D stand for in 205 75D15?
The D stands for diagonal or bias ply construction. That means the tire body plies inside the tire will crisscross. The 15 is the wheel diameter in inches and the C after the tire size will designate the load range. The load range C is a 6-ply rated tire.
What does the D and R mean on tires?
Expert Reply: The difference between the two trailer tire sizes is that the letter D in the first size you listed ST205/75D15 stands for bias ply and the letter R in the tire size that they put on your vehicle stands for radial.
What is a radial tire vs bias ply?
A radial trailer tire is constructed with steel belts of the tire running at a 90 degree angle of the tread center line. A bias ply trailer tire is constructed with nylon belts of the tire running at a 30-45 degree angle of the tread center line.
What does D mean in tire size?
diagonal
D is for tires built with diagonal (crisscrossed) plies, called bias-constructed tires. They are also called conventional, x-ply, or cross-ply tires. Some motorcycle and trailer tires still use this internal construction.
What’s the difference between D and R tires?
The difference between the two trailer tire sizes is that the letter D in the first size you listed ST205/75D15 stands for bias ply and the letter R in the tire size that they put on your vehicle stands for radial.
What’s better for a trailer bias ply or radial?
Radial tires tend to flex more than their bias ply brethren, which provides for better traction, stability, and tread wear. Radials also tend to run cooler—especially under load.
Why radial tires are better?
“Radials offer lower fuel consumption, better traction and flotation and improved cut resistance in the tread area, and run much cooler than bias.” “Radial advantages are pretty much across the board,” agrees Wright. Typically they offer longer tread wear and a smoother ride.
Can you mix R and D tires?
Expert Reply: It’s fine to use a radial-type tire as a spare (a tire with “r” in its size code) with a trailer that has Bias ply “d” tires but for a short distance in the event of a flat tire. But mixing tires is not recommended for everyday use because their internal construction is different.
Can you mix bias ply and radial tires on a trailer?
It is important to never mix bias and radial tires on the same trailer. Likewise, tires should be of the same size and load rating on all axles and inflation should be checked before each outing. Just like with trucks, brand and age should be the same, when practical.