Advice on Tires for a Boat Trailer

Updated 05/05/2018 | Published 05/04/2018

Products Featured in This Question

Kenda 5.30-12 Bias Trailer Tire with 12" Galvanized Wheel - 5 on 4-1/2 - Load Range C

(7215)

$86.85

Taskmaster 5.30R12 Radial Trailer Tire - Load Range C

(285)

$102.91

Question:

I have been running a pair of AM30850s on a boat trailer that hauls a 1979 Boston Whaler Montauk 17. They are almost 5 years old and have been rock solid with respect to holding air. Normally run at 59-60 psi. We routinely run 1 1/2 hours each way at 60mph to regatta venues. This past weekend we were running about 4 hours with speeds to 70mph. On arrival I noticed that the left was soft, down to about 25 psi. The right was fine. I topped it up and the next day the right had dropped to about 25 psi. Since this happened the left has stayed pretty solid, but the right has slowly lost it again, down to 25 psi over the course of a week. Are they just getting old, couldnt handle the speed/heat? Barring an obvious puncture, is there some high tech reason the tires would act strangely. I reduced the diameter over the original tires that came on the trailer to help with launching and recover of the boat and increased the load range to run higher psi for less rolling resistance. Is there another wheel/tire combo that might be wider and help with spreading the load at speed? Any thoughts appreciated.

asked by: Wilson Z

Helpful Expert Reply:

I would guess that your problem is a combination of a number of things. First off they are getting old. We usually recommend getting new trailer tires at about 5 years and definitely keeping them no longer than 7 regardless of the mileage on them.

Also, the # AM30850 tires have a maximum psi of 80 psi. Trailer tires should always be inflated to their maximm psi when they're cold. Since you're only running yours at around 60 you're not getting the full capacity of the tires and you're actually causing them to heat up more than they should; which will shorten the life of the tire.

In addition to that your tires have a maximum speed rating of 65 mph which you were exceeding this time, although not by a lot. I'd be less worried about this if you were running at the correct 80 psi.

Instead of worrying about a wider tire to use I would keep the size and load rating the same and switch to a radial tire, like the Taskmaster # TT53012C. Radials flex more and therefore have better contact with the road. If you're generally towing on highways it's definitely the way to go. Other than that just stay within the weight capacity, speed rating, and inflate them to the max psi. The Taskmasters are rated up to 1,050 pounds at 80 psi, but also have an 81 mph speed rating.

expert reply by: Charles S