Trailer Tires

[John M.]

What is a good brand/type tire to use on a trailer that is carrying heavy, valuable cargo such as vintage cars and also pampered horses (different trailer). The guy who sells trailers has tires that look like junk and cost big bucks. Are the tires special? In what way? Thanks for any help.

[Duke W.]

Re: Trailer Tires

First, what size or size range will the wheels and fenders accept.

Once this is determined, find a passenger car tire in this range with at least a "H" speed rating, and verify that it has a nylon cap belt.

Assuming the trailer has 15" wheels of sufficient width, a V-rated police pursuit tire in a 225/70-15 or 235/70R-15 would be good choices.

Four 235/70s have a combined load capacity of 7496 pounds at their maximum cold pressure.

If you search The Tire Rack for suitable sizes and speed ratings and click on "specs" for each tire you view, you will see the technical information on each tire. Similar specs for each tire are also available on tire manufactureres' web sites, and the casing/belt construction, service description (load index and speed rating), and load capacity are molded into the tire sidewall.

If you have the last couple of issues of The Corvette Restorer, review the tire articles. Selecting tires for a trailer isn't fundamentally different than for a Corvette, however, with a trailer, you want to pay particular attention to tire load capacity. Buy as much speed and load capacity at you can fit on the trailer wheels and physical space. The greater the speed and load capacity, the more safety margin you have.

Duke

[Mike Cobine]

Re: Trailer Tires

I have to respectfully disagree with Duke on this. He has had excellent articles on car tires and has done a lot of studying on the subject, but ...

Trailer tires are designed for a different environment and loading than a passenger tire. That is why you see true trailer tires marked with the ST designation. They typically have a more rigid sidewall.

Many years ago, it was a well-known "fact" that you should not use radials on a trailer. However, today you do see radial trailer tires. Some are simply passenger tires with a high load rating that work and others are specialty trailer radial tires. Don't use a passenger radial. The sidewalls are too thin. This allows excessive squirm of the tread on the pavement and builds up heat. Heat is your enemy and causes tire failure. Use at the minimum a light truck LT radial and preferably an ST radial.

You also see a lot of cheap used passenger radials on trailers sold new to cut costs. Figure you are safe to get the empty trailer home. This is a true example of "penny wise, pound foolish".

You didn't mention the trailer size or maximum load rating. While passenger tires often function on open trailers for the reasons Duke stated, they are not going to work on a large heavy enclosed trailer where the maximum load rating far exceeds the passenger tire ratings.

You don't want your tires to be rated at the exact same amount that the trailer is. Otherwise, when the trailer is at maximum, the tires are on the verge of failure. Wells Cargo had 12,000 rating for the tires on their 10,000 GVWR trailers.

Trailers typically have an oscillation to them, the swaying back and forth. It may be large, as ones that look like they will fly off the road any second, or it may be very small, enough that they look like they are towing straight. But the nature of a trailer is that it sways back and forth unless everything is perfectly equal, and in the real world, it rarely is.

This sway over long miles generates lots of heat, and can cause treads to rip off. Look at all the boat trailer tires on the highway.

Heck, look at all the big truck tires on the highway and that industry has been working for decades to prevent that problem.

Trailer tires tend to hit more objects than the towing vehicle. Often this is from the right wheels being on the edge of the pavement or the shoulder. The tires on most trailers track outside the track of the towing vehicle and so while you steer to miss something with the truck, the trailer probably hits it.

The left wheels tend to impact the reflective markers and this constant impact eventually leads to tire failure.

So you need tough tires that can take a beating and survive.

Most good tire stores that also service truck tires, especially commercial truck tires, will have what you need. Goodyear, Cooper, Dayton, Firestone, Bridgestone, Kelly, and others make quality trailer tires.

Do not run mobile home MH tires. While I have many thousands of miles successfully with them, they are not designed for that, are cheaply made because of their intended use, and tend not to last even one fourth of the time a quality trailer tire costing less than double will last. They are a poor value. If you are stuck with a trailer running those open style 14.5 inch diameter wheels, you can get Low Boy ST and LT rated tires to fit.

If you are traveling cross country at all, have two good spares. If you lose a tire, you will find yourself with no spare and now at the mercy of anything available along the road. This can prove to be expensive and a mismatch of tires, in tread and size. The size on the side may be the same, but the tires of different manufacturers of trailer tires can be very different in actual width and diameter.

The bottom line is this: you are hauling a vintage car worth $30,000 +/- $20,000. Is it worth risking that amount just to save $50 on tires?

Horses. There are some horses that the value is such you wouldn't even be here asking such a question. So we will assume that yours are more sentimental value. Do you want to risk them?

If your sales guy's tires look like junk, then go elsewhere. You won't find them at every Pep Boy's, Tire Kingdom, K-mart and WalMart, but you can find them in nearly every decent-sized town. Go look elsewhere.

[Mike Cobine]

Re: Trailer Tires

Rereading my note, it may imply trailer tires should be radials. Actually, most are not. Radial trailer tires are in the minority. Having a non-radial cost more than a radial is hard for some people to accept and so they go for passenger car radials assuming they are better than non-radial trailer tires.

And also, it may imply that Duke suggested radials. He did not. He gave tire sizes that were non-radial for all but one.

[Duke W.]

Re: Trailer Tires

Speed and load is speed and load whether on a trailer or car. The guys I know who tow trailers have had less than satisfactory experience with bias-ply trailer tires, and excellent experience with radial tires. Many trailer tires seem to be of less quality that the highest quality passenger car radials such as the police pursuit tires I mentioned all of which are V-rated radials.

It comes down to the size of tire or size range that the trailer can accomodate and knowing the gross weight of the trailer. If you can find higher load and speed rating in an suitable size passenger car tire than a trailer or light truck tire, I would go with high speed rated passenger car radials.

Duke

[John M.]

Re: Trailer Tires

Thank you guys, very much. The horse trailer is rated at 6000 lbs, (it's for two horses)I think 215 or maybe 225s will fit. So it's either speed and load rated passenger or ST or LT rated truck/trailer tires? The horses (daughter's) have the same sort of sentimental and monetary value as a midyear.
BTW I just checked the tires on my (open) car trailer and they are are load range B, 1480lbs. 205-75D15 ST, "for trailers only". Seems a little light at 5900lbs.?

[Michael S.]

Drive your car

and you will not have to worry about something as silly as trailer tires. Seriously, buy the best tire you can afford. I have found the Goodyear "Marathon" radial trailer tire to be HORRIBLE! I will not make suggestions as to what you "should" run, however I can tell you what NOT to run

Mike Strinich
#11202

[Warren F.]

Re: Trailer Tires

John: I have a Featherlite enclosed trailer w/living quarters that I haul my '71 LS6 coupe to shows back east. The trailer weighs 14,140lbs with car in it. I have 235x85x16 Load E 10ply Uniroyal Laramie tires, they are LT rated. My trailer was just over $82,500 in cost along with a Corvette at about $85,000 in value, trailer is a 42ft gooseneck. As others have stated buy a heavy duty quality tire. Good luck!

[Don G.]

Re: Trailer Tires

I won't advise you what tires to use but based on my experience, I will only use tires specifically designated for trailer use ( due to sidewall construction) of a load range that is greater than trailer GVW from a reputable manufacturer. I agree with Mike's assessment including the two spare recommendation.

[Chuck G.]

Re: Trailer Tires

I'll add my "two cents" worth, and have my flame retardant suit on I have a 16 foot open trailer. I've had it for about 15 years and have done a LOT of towing with it....my Corvette's, other's Corvette's, other cars, etc.

I use regular "car" radial tires. As a matter of fact, I usually buy "take off" used tires from the Goodyear dealer across the street from my office. I usually pay about $5.00 per tire, as this is what it would cost him to dispose of them. Never have had a problem, or a blowout, or any tire failures.

Know nothing of HD tires used for "box" trailers. Chuck

[Patrick H.]

Re: Trailer Tires

Chuck,

The open trailer I use has tires that were "take offs" from a Suburban. They track and pull far nicer than the original trailer tires. The trailer owner plans to use the same type again when he has to replace them. So far we have several thousand miles on the trailer, from Georgia to Oklahoma to eastern NY and Hershey PA, and several Bloomington trips.

Patrick

[John Walker]

Re: Trailer Tires

Guys; I work for a company that uses stock trailers and specialty trailers in both fifth wheel and pull style and we ( the company) has used good quality LT rated tires for years and many hundreds of thousands of miles with a very low failure rate. Buy a good quality tire with many outlet dealers ( for service conveiniance) and take good care of them. Duke has a point about getting a load rating above the gross physical weight envisioned.... but going to far over is a waste of money. By the way most of our trailers weigh in excess of anything you will weigh with the enclosed trailer and car. John

[Zachary K.]

Re: Trailer Tires

I need help with tire information. I recently traveled across country and this is all way too familiar. Whoever mentioned about having two spares is 100% correct. I had to replace a tire that blew out and then had a flat that was repaired but then developed a bubble.

I couldn't replace exactly what was on the trailer while I was on the road, but purchased a B.F. Goodrich T/A radial. To get me rolling again. Now I haven't kept up with tire sizing and ratings, so can someone help me out. I have looked this tire over and have seen nothing of what I can tell is a rating system other than Treadwear 400 / Traction A / Temperature B. The Load rating at 1433lbs. is definately more than I need as my car and tailer combined probably weigh in the neighborhood of 5500lbs. The size is P205 70R 14 M & S(this I understand) what follows is 93S and then there is an E4 that is circled is this the rating that you speak of? The trailer is a twin axle and I have purchased another B.F. Goodrich T/A radial of the same size to match the other on the same axle. My other misunderstanding or confusion comes as the original trailer tires which are trailer only tires have an air pressure limit of 45lbs where the T/A radials have a 35lbs. limit.

Should I purchase two more T/A's to match the others so all four will have the same air pressure? Reading these post sure has me wondering!!! Thanks for the help or whatever advice you can give.

[Terry M.]

Re: Trailer Tires *TL*

Zac,
The number 93 is the tire's load index, the letter S is the speed rating. S = 112 mph and 93 = 1433 lbs. See the link for more.
Sorry but I can not offer any authoritative advice on trailer tire selection, but I am sure others will.




Tire Rack tire tech

[John H.]

Re: Trailer Tires

I'm no expert, but I had many thousands of miles of good service when I had an enclosed trailer using trailer-rated tires whose rated max load capacity (for all four tires combined) was about 1500# more than the loaded trailer weighed (5200#). The Radial T/A's are an "economy cosmetic performance" passenger car tire, with no cap belt, and under your load conditions, are on the ragged edge of their load capacity. I'd go looking for a full set of trailer-rated tires whose load capacity gives you some safety margin - you have none with the T/A's, and that's not a good thing.