Trailer tires, radial vs. bias ply

well you asked.... so my opinion based on personal experience with both on a pop up camper-

RADIAL.

In recent times I have seen Bias, Radial and Diagonal ply tires. Every maker will tout the advantages of their design.

ST tires are designed by the tire industry for Trailer use and are found on most Horse, utility and RV trailers from the factory. They are designed for straight line pull and most are limited to 65 mph. They have stiffer sidewalls.

LT tires are designed by the tire industry for light trucks, they are often rated to 75 mph and the tread varies for the type of service they are intended for, typically a blend of highway and mud and snow service. There are far more choices of tread and load ratings. People sometime prefer them for TT use because of the more rigorous testing they have to undergo; though the tire industry does not advertise them for such.

P tire are for Passenger car service and are often found on half tons and SUVs. They provide a smooth and comfortable day to day ride. It is not unusual for folks to increase the tire pressure when towing to stiffen the ride.

I use ST radials on my TT because they are supposed to have less rolling resistance.

Some of the Vintage era TTs used car tire because there as nothing else.

time2roll wrote:
I would stick with ST or LT radials at time of replacement.
Get tires rated to carry the full GVWR.

CONCUR on both !

Lwiddis wrote:
I understand from a number of sources that passenger car tires don't have the stiffness in the sidewalls to safely handle a travel trailer.

Yes! x2

You will have some people on this forum say if you run P's on a trailer you will kill every single man woman and child that's on the road you're on.

We ran P tires on our car trailer for years. After 23 years one threw the tread off of it. It still held air though. We just put a new set on and kept on towing.

I ran bias up till a few years ago. I liked them "slightly" better than SBR for towing. Check out the difference between the side wall and you will know why I liked them better.

I don't like SBR because they tear things up when they go. Bias just goes to pieces and that is that.

That being said I do have a set of SBR on my trailer now. Bias were getting too hard to find on the road.

Turtle n Peeps wrote:
You will have some people on this forum say if you run P's on a trailer you will kill every single man woman and child that's on the road you're on.

That's a fact! An alternative one, anyway.

Really you can run any tire on a trailer that you want as long as it meets the weight requirements, but the towing experience can vary. I've seen P metrics on landscape, cargo, and popups that work just fine. These trailers have a pretty low center of gravity and normally not all that heavy. You normally don't run into issues when running passenger tires in those situations. Really if the travel trailer is light enough then you can get away with it just fine.

However, longer high walled travel trailers have much higher center of gravity and greater weights so flex in the P metric sidewalls can induce sway. I'd stick with ST or LT tires for anything with a decent weight.

There is a thread currently running on the Airstream Forum about using Michelin LT tires on trailers. A member contacted the headquarters and Michelin does not advise using their LT tires on trailers. As a matter of fact they went on to say that doing so will void the warranty. Many continue to claim the benefits of the "stronger" LT tire out weighs the risks. Apparently it remains a popular option regardless of what the factory is saying.

It may be true that you can (and folks have) run most any tire on a TT but it makes sense to select the tire designed for the job. It is often a matter of improved technology.

I think the fact that the RV industry puts over a million ST tires on the road every year pretty much tells you they have optimized the cost to performance issue.

There may be better options but it is up to the consumer to justify their choice. The TT industry is going to stay with what works.

A member contacted the headquarters and Michelin does not advise using their LT tires on trailers. As a matter of fact they went on to say that doing so will void the warranty. Many continue to claim the benefits of the "stronger" LT tire out weighs the risks. Apparently it remains a popular option regardless of what the factory is saying.

Old old stories from the RV world what Michelin says when asked a certain question such as asking for a LT tire for direct replacement for ST tires on a trailer. This story has been around for years and refuted time and time again. Michelin XPS Ribs are recommended for commercial trailer service. We run these tires on our trailers in commercial service for 50k-70k miles.
Now if you were to ask Michelin like this posters email stating; (snipped for length)

**In regards to the email you sent stating:
I have a 2006 Montana 5th wheel Trailer that has two 6,000 lb Dexter axles and 4 deluxe aluminum Rims each rated at 3,042 lbs. I would like to install your Michelin XPS® Rib™ LT235/85 R16/E's on this 5th wheel. Will the tires be fully waranteed in this application?

Answer..---------------------------------------------------------------------
We appreciate your request for information regarding the Michelin XPS Rib. The XPS Rib, size LT235/85R16/E, part number 13080 would be a good fitment for your 5th wheel. The tire carries 3042Lbs at 80-psi max pressure. For best pressure recommendation, run at maximum pressure until you can weigh your axles either call or reply to this email for a pressure recommendation.
It is a good application, so there are no warranty issues. Your tires are covered under applicable warranty.
We appreciate your business and thank you for choosing Michelin.

It is our goal to ensure that your issue has been resolved or your question answered to your satisfaction. If we can assist you further, please respond to this email or call us at 1-800-642-4354 (toll free) between 8:00AM and 8:00PM Eastern Time Monday through Friday or between 8:30AM and 4:30PM Eastern Time on Saturday.

Sincerely,
Diana
Consumer Care Department
Certified Michelin Product Expert*** (end of email)

So as we see depending on your agenda we can back Michelin or any LT tire maker into the liability corner with a certain phrased question we can get a not recommended answer.

Or if your looking for the best tire for your trailer that can last 40k-60k miles and 8-10 years of service we can get a positive answer all depending on the question and ones agenda.