What is the Difference Between a ST205/75R15 Tire and ST205/75D15 Tire
Question:
What is the difference between a 205 75R15 and a 205 75D15? And can I use the D15 as a spare tire?
asked by: Lea
Expert Reply:
Due to how differently radial and bias tires will run, we do recommend all tires match. Bias ply tires will run hotter and stiffer than Radial tires so it can affect the ride and wear of both tires.
With that being said, the D designation you are referring to in something like the Loadstar ST205/75D15 # AM1ST92 will mean it is a Bias Ply tire and the R in something like the Karrier ST205/75R15 # AM10244 will refer to the tire being Radial.

Products Referenced in This Question
Karrier ST205/75R15 Radial Trailer Tire - Load Range C
- Trailer Tires and Wheels
- Tire Only
- Radial Tire
- Load Range C
- 205/75-15
- 15 Inch
- M - 81 mph
- Kenda
more information >
Loadstar ST205/75D15 Bias Trailer Tire - Load Range C
- Trailer Tires and Wheels
- Tire Only
- Bias Ply Tire
- Load Range C
- 205/75-15
- 15 Inch
- Kenda
more information >
Product Page this Question was Asked From
Loadstar ST175/80D13 Bias Trailer Tire - Load Range D
- Trailer Tires and Wheels
- Tire Only
- Bias Ply Tire
- Load Range D
- 175/80-13
- 13 Inch
- M - 81 mph
- Kenda
more information >
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