Difference Between D and R 215/75-14 Tire Sizes

Updated 08/12/2022 | Published 08/11/2022

Products Featured in This Question

Provider ST215/75R14 Radial Trailer Tire - Load Range C

(1094)

$123.23

Provider ST215/75R14 Radial Trailer Tire - Load Range D

(1094)

$152.37

Question:

I have 2 tires one a 215/75R14 and the other a 215/75D14, why is the 75D14 so much taller than the R14?

asked by: Joseph D

Expert Reply:

The D stands for "Bias" while the R stands for "Radial". Bias tires have a stronger sidewall and are usually used for off-road applications like agricultural trailers (although they can be used for highway-type trailers) while Radial tires have a little more flex in the sidewalls which helps keep them cooler at higher speeds so they are more ideal for highway usage.

It's always a good idea to use the same ply-type on the trailer since their sidewalls have different amounts of flex as you've experienced. To swap out your Bias tire to a Radial tire I recommend using the Taskmaster # TTWTR21514 if you have a Load Range C or the Taskmaster # TTWTRTM2157514D if you have a Load Range D tire.

Attached are some review videos for you to check out.

expert reply by: Jon G