Posted 2014-08-13 6:59 AM (#160384) Subject: Need Advice on Trailer Tires
Member
Posts: 26
I bought a 2 horse trailer a few years ago. It was a used trailer but had never been used (if that makes sense!) Recently I noticed some dry rot on the tires so I started looking into getting them replaced. I then noticed I had P tires on the trailer, not LT or ST. Do some manufacturers put passenger tires on trailers? I don't see where the first owner would have switched them out.
I am also wondering about what size I can get. The size on there now (235/75/15) does not come in ST. Is there a comparable size that would work? Or would LT tires be okay? I am going to call the local tire stores but I want to make sure they give me the right information. Thanks!
Posted 2014-08-13 8:37 AM (#160387 - in reply to #160384) Subject: RE: Need Advice on Trailer Tires
Veteran
Posts: 233
Location: Pataskala, Ohio
I use only LT tires on my trailers on the advise of my cousin a Goodyear commercial tire store manager. The larger the tire you can get under the trailer the more weight the tires can handle.
Posted 2014-08-13 9:12 AM (#160388 - in reply to #160384) Subject: RE: Need Advice on Trailer Tires
Expert
Posts: 5870
Location: western PA
If passenger tires are installed on trailers, most tire manufacturers will void any warranty. Some times it's possible to get more capacity with a P tire, but if problems occur, you're on your own.
As was previously stated, a LT tire is the best. If a wider tire will fit within the wheel well, it will offer a larger carrying capacity. Switching to a higher load rating, will also increase the tire's longevity and safety.
Posted 2014-08-13 9:56 AM (#160389 - in reply to #160384) Subject: RE: Need Advice on Trailer Tires
Elite Veteran
Posts: 789
Location: Tenn/Ala.
For what it is worth- as taught in the tire fitment classes to employees of the tire manufacturers:
When a P tires is fitted in a light truck service application, the load rating is to be calculated with a 10% loss of capacity. This is due to the different forces applied to a tire by a light truck than a passenger car, primarily caused by the higher center of gravity transferring more weight to the outside tires during cornering situations .
I am quoting that from memory almost 25 years ago, but I'm pretty close. And I have always used the same logic when seeing a P tire on a trailer application.
And yes, I have seen some of the lower end units from smaller manufacturers use P tires on new trailers before. I would probably look at a good ST225/75R15 tire. We've had good service with them, and you'll have a hard time actually finding a LT 15" tire in stock anymore.
RTSmith
Posted 2014-08-13 10:29 AM (#160391 - in reply to #160389) Subject: RE: Need Advice on Trailer Tires
Member
Posts: 26
Thank you! That explains a lot. I don't haul very often but I had 2 horses in there a couple of weeks ago and got a lot of scary sway on the highway that I never felt before. I am going to be buying new tires before I haul anywhere else.