Can I Use A ST 225/75/D/15 For A Spare Tire In Place Of A ST 225/75/R/15

Updated 10/22/2019 | Published 10/21/2019

Products Featured in This Question

Karrier ST205/75R15 Radial Trailer Tire with 15" White Wheel - 5 on 5 - Load Range C

(1575)

$191.55

Loadstar ST225/75D15 Bias Trailer Tire - Load Range D

(3903)

$143.18

Question:

Can i us a St 225/75/D/15 for a spare in place of a ST 225/75/R/15

asked by: William L

Expert Reply:

Yes, you can use a ST 225/75/D/15 like the Loadstar # AM1ST96 for a spare in place of a ST 225/75/R/15. While there are differences between radial and bias-ply tires, they are not significant enough to make a difference for spare tire use unless you foresee that spare seeing active use long term after replacing an existing tire.

A bias tire has a stiffer sidewall and might be used more on off road applications, like farm use.

Because of the construction of a radial tire, the tire has more flex and will allow for more ground contact. That will improve traction and better tread wear. It also gives the radial tire better stability. The radial tire will normally run cooler, if not overloaded, which will help the tire last longer, especially when the tire is under a load.

expert reply by: Patrick R