Newbie tire question

[jornvango]

Today, I noticed that one of the 4 tires on our 21' AS Sovereign is worn towards the outside. The inside has plenty of thread left but the outside is almost slick.

The other tire on that axle has similar wear, but there is some thread left so it look OK.

Newbie tire questions:

- Is this 'normal' and can it be avoided by rotating the tires?

- The tire says "load D". I assume we can just replace the tire with another "load D" tire (of the correct dimensions) at a place like Discount Tire? No need to get a special 'trailer tire' if there is such a thing?

- Since the one tire is almost a slick, I'm assuming it's in urgent need of replacement. Do we replace just the one tire or is it necessary to replace both tires on 1 axle at the same time?

- I checked the psi and all tires have around 38 psi cold. However, the AS sign on the outside of the trailer, it shows that tires should/can have 50 psi cold. Is this the psi that we should keep the tires at, or is that sign indicating the max psi when the trailer is fully loaded?

Thanks!

[SteveH]

Oh Boy! Lots of questions, and a topic that has lots of threads.

Tires that are worn irregularly can be caused by several things, and on a trailer one thing could be axle alignment. Another could be improper inflation, and a load range "D" tire should be at 65 psi cold.

About the replacement, I would first check the age of all the tires, and there is a code stamped into the inner side wall of the tire. It's a four digit code which represents the week and year the tire was manufactured. Trailer tires "ST" for special trailer have a history of failing with age before actually wearing out.

There is so much information on here about tires, I suggest you do a search and start reading. Lots of information.

[Jammer]

Originally Posted by jornvango

Today, I noticed that one of the 4 tires on our 21' AS Sovereign is worn towards the outside. The inside has plenty of thread left but the outside is almost slick.

The other tire on that axle has similar wear, but there is some thread left so it look OK.

Newbie tire questions:

- Is this 'normal' and can it be avoided by rotating the tires?

It is not normal and probably indicates that the axle components are bent or misaligned.

- The tire says "load D". I assume we can just replace the tire with another "load D" tire (of the correct dimensions) at a place like Discount Tire? No need to get a special 'trailer tire' if there is such a thing?

The question of the best replacement tire is controversial and opinions are diverse. Type ST trailer tires are available and have been used on most trailers by the factory for some time, and are a replacement option to consider. Some people use type LT truck tires, but you may find that they are not available in a suitable size and capacity, depending on your situation.

- Since the one tire is almost a slick, I'm assuming it's in urgent need of replacement. Do we replace just the one tire or is it necessary to replace both tires on 1 axle at the same time?

Check the age of your tires as described upthread, if they're ten years old or more, think about replacing all four. Otherwise, just replace the bad tire, and get your axle problem solved.

- I checked the psi and all tires have around 38 psi cold. However, the AS sign on the outside of the trailer, it shows that tires should/can have 50 psi cold. Is this the psi that we should keep the tires at, or is that sign indicating the max psi when the trailer is fully loaded?

Thanks!

You should inflate the tires to the pressure indicated on the placard.

[Phoenix]

You state that the tire is "worn toward the outside". Do you mean that the outside and inside edges of the tire are worn slick, and the center portion still has tread? If so, the tires are under-inflated. Also, if the tire placard indicates 50 psi, you should be running 50 psi in them, not 38.

The 50 psi call-out would seem to indicate that your Airstream originally came with load range C tires. The load range D tires you have now probably have "65 PSI Maximum" printed on the sidewalls. You may wish to consider running this higher pressure.

It sounds like you are due for a new set of tires; and as others have suggested, it would be in your best interest to read up on tires on this forum.

Quick answer: Strongly suggest you replace all four tires. While load range C or XL tires may work on your Airstream, I'd seriously consider purchasing ST (special trailer) or LT (light truck) tires in load range D (65 psi max) or E (80 psi). The decision to switch to 16-inch wheels and LT (light truck) tires is another alternative, and you will find that many have switched to LT tires due to ST tire failures (tread separation and blowouts).

To avoid duplicating info from other threads, I am sending you some links to suggested reading via PM (private message).

[jornvango]

Axle components bent or misaligned? That sounds expensive. Where would be a good place to have this checked/fixed: an RV place or a regular car mechanic?

[SteveH]

Originally Posted by jornvango

Axle components bent or misaligned? That sounds expensive. Where would be a good place to have this checked/fixed: an RV place or a regular car mechanic?

To actually align the wheels takes a machine that bends the axle. There may be more, but I know of only two places in Texas that will do it, one is a truck shop on IH35 just on the North side of Waco, and the other is North Dallas RV, of course in Dallas.

[ZoominC6]

May I suggest that when purchasing new tires, check the date of manufacture on the tire code imprinted into each tire. You want freshly manufactured tires and I suggest changing them every five years on trailers, not ten, no matter how often you might use them. Dry rot is dry rot. Good luck.

[Bill M.]

Are thes the tires that came on the trailer originally? Generally the tag on the trailer has a tire size and a inflation pressure.
Do you have steel wheels or Aluminum wheels? If you have the steel wheels most likely the proper replacement tire is a ST 225/15 load range C run at 50 psi. Many people opt for a P metric like the Michlen LTX in 235/15 XL, run at 50 psi. If you have aluminum wheels then you can run the load range D tires in either ST or LT. If the tires are the original, or are of unknown age, I would replace all of them. A lot easier at home than on the road after you pick up all the damaged wheel well parts and sheet metal from the trailer. In my opinion trailer tires are critcal and not a good place to save.

[BlackAces]

If you are a NASCAR fan you may have seen the mechanics on pit road do this quick check.

Trailer Tire Problems & Tips

BlackAces

[jornvango]

We took the trailer to Discount Tire. They replaced the bad tire with a Carlisle Radial Trail RH Trailer Tire ST225/75R15E1 117 B.
They also noticed that the other tire on that axle was about 9 years old, so we also replaced that tire with the same kind.

The trailer tires used to have about 38 psi. The Airstream placard shows 50 psi. Discount Tire recommended (and applied) 80 psi. I hope they know what they're doing

P.S. Here is the product link on the Discount Tire website: Carlisle Radial Trail RH Trailer Tire 225/75-15 Tires in the Austin Area - Discount Tire/America's Tire

[Zigidachs]

There is a plethora of information on this forum. Many options! Lots of great advice.
After exploring the forum, and speaking with several "experts", we decided to purchase the 16" LT Michelins--Load Range E, carry the psi at 78-80, and rotate the tires every 5k miles to inspect for damage, balance and wear. There are pros and cons to this approach, but it seems the safest for us. We have had absolutely no problems. Good luck, and safe travels......Zigi