Can a Trailer Spare Tire be Slightly Smaller in Diameter than the Rest of the Tires

Updated 06/09/2014 | Published 06/07/2014

Products Featured in This Question

Karrier ST205/75R14 Radial Trailer Tire with 14" Galvanized Wheel - 5 on 4-1/2 - Load Range C

(2390)

$162.60

Loadstar ST185/80D13 Bias Trailer Tire with 13" White Wheel - 5 on 4-1/2 - Load Range D

(2699)

$165.67

Question:

I have an RV and it did not come with a spare tire. The tires on the RV are ST185/80R13, which if I wanted that exact tire it would be a special order. There is a similar tire on the shelf at a neighborhood hardware store that is ST175/80D13. Could I buy this tire and use it only as a spare tire to get me home safely? I know that the spare tire or donutinch on most cars is smaller than the normal tires. I figured the same would apply here as well. Thanks!

asked by: Brady S

Expert Reply:

Typically we recommend the use of the same tire size when picking out a spare tire for a trailer, but since the overall tire diameter difference between the two tire sizes you listed is only .3 of an inch you would be fine for just getting the trailer home or to a shop.

If you aren't in a hurry to get the spare tire I would recommend that you order in the correct size tire just to be on the safe side. If your wheels have a 5 on 4-1/2 inch bolt pattern you would want the Loadstar ST185/80D13 Bias Trailer Tire with 13" White Wheel # AM3S331. I attached an FAQ article on determining wheel bolt pattern for you to check out.

I attached an FAQ article on trailer tires for you to check out as well.

expert reply by: Jameson C