Can a 4.8-12 Trailer Tire be Replaced with a 145/80-12 Trailer Tire

Updated 10/03/2011 | Published 10/02/2011

Question:

Currently have 4.8-12 on 12 inch rims. Would like to switch to S-Trail ST145/R12 for weight capabilities. Will this tire fit this rim? If not what tire will fit and give me an increase in towing weight capabilities?

asked by: Charles C

Expert Reply:

Both the 4.8-12 and the 145/80-12 will fit on a 4 inch wide rim. However, the 145 will be taller by about 13/16 of an inch so you will want to make sure that there is space above the tire for the larger size. The 145 will also be wider by nearly an inch so you will want to make sure you have space between the back side of the tire and the trailer for the wider overall size.

Adding a trailer tire with a higher capacity will not allow you to carry more weight. You have to go by what the trailer is rated for. This is the axle capacity or trailer capacity that is indicated on a sticker or plate on the trailer frame. The trailer can only carry as much weight as the weakest link in the system. So whatever has the lowest capacity, that is what you must go by. I have included a link to our trail;er tire FAQ article for you.

expert reply by: Michael H