Uneven tire wear..Yikes!!

[daydreamer36535]

Hi all,
in preparation for a trip I was checking the tires out and have found
a problem i'm confused/concerned about.
see pic at http://www.gulftel.com/3strong/tire1.jpg
http://www.gulftel.com/3strong/tire.jpg

This is on a 1974 ambassador, 29'.
So, dual axle and the problem is on one side only.
I see no loose bolts ect.
also it seems this problem occured within the last 1000 miles as I just checked the tire pressure before coming home on the last trip.
As you look at the tire, there is deep wear for 2-3" then all is well
for about 6" - 16" then another deep wear pattern, all around the
tire. This occured on both tires. Its almost like the tire is trying to become square in spots.


What could be the cause?
thanks
Joe

[drboyd]

...balanced?

[overlander64]

Greetings Joe!

When I had abnomal wear similar to yours, it was caused by problems with the brakes on the streetside of my Overlander. The drums had worn to the point where the shoes were catching on ridges within the drum causing the brakes to lockup in a "chatter-like" maner both when stopping and starting. There was so much road construction where I was traveling that I attributed the braking shudder to the construction so wasn't terribly alarmed - - it was only after returning home that I discovered the damage to the nearly new Good Year Marathons. The solution on my coach was to replace all of the brakes with new fully loaded backing plates along with full machining of the brake drums and machining the shoes to match the drums. According to my mechanic, the trailer tires would drag from 3' to 5' each time I started or stopped which resulted in the spotty wear along with the fact that the pulsing action created as the shoes caught on the drums also caused periodic locking of the wheels when using the brakes to slow as well. On my coach, the damage occurred during the last 500 miles of a much longer Caravan.

Good luck in locating your tire wear gremlin!

Kevin

[Silvertwinkie]

I'd guess inflation/balance or the rig sitting for too long in one spot underinflated.

[wingfoot321]

Have never had this on a trailer. Have had it on front tires on cars and trucks. Usually indicates a problem with tow-in or alignment.

Any chance that you hit something hard enough (pothole or curb) to knock one side out of alignment.

[overlander63]

The last time I saw tire wear like this, was on the back of a front wheel drive car.
It turned out the rear shocks were worn out, and were letting the tire bounce a little as it went down the road. After a few thousand miles, the tires wore to the point where they were hopping up and down, and, of course, making the wear that much worse.
The "bounce test" that we do with automoblies, will not work on these trailers. As far as I know, the only way to check the shocks, are to remove them, and see how easy it is to extend and compress them. Also check for oil leaking out of the innards of the offending shock(s). Anybody with an easier way to check these, please, jump in and say something.
Something else to check is if you wheel bearings are too loose, that will cause a wierd wear pattern, also, although usually on the inside edge of the tire, not all the way across.
Terry
(in Florida)

[daydreamer36535]

Well,
It turned out to be worn out axles.
warped front to back.
Gonna repalace the whole thing x 2.. bearings hubs brakes ect.
also 4 new shockes while the things are down.
Thanks to all,
Joe

[wingfoot321]

Did you get anymore detail explanation? What causes this to happen? Do you know if it is a fairly common occurence? How do you check for warped axles ? It seems like some event should precipitate the warping of both axles.

[Inland RV Center, In]

Scalloping, as it is called, usually happens from a number of things.

Lack of or improper running gear balance (tire, wheel, hub and drum as an assembly).

Bad shocks.

Improper alignment.

The rubber rods in the axle have become defective.

Improper inflation.

The more of these things that are wrong, bad, or incorrect, the worse the scalloping.

It can happen on one tire, or all of them.

Andy

[DPeakMD]

Those pictures make it look like it's definitely an axle problem. I would suspect improper toe-in or toe-out. If the wear is on the outside of your tire it's toe-in.

The correction for this is to measure the amount of toe misalignment and then basically 'bend' the axle back into alignment. There is a list of places which will provide this service accessible from the Airstream website as a download. Of course, you could also be ready for new axles for other reasons and this would correct it, too, since that's set at the factory.

Make sure you and everybody who works on the trailer is aware not to use the axles as a jacking point. This is a serious 'no-no'. You're probably already aware of this, but there are many who are not, and this may have been done by a prior owner.

I'd make sure your replacement shocks are for the Airstream. They're made by Monroe, but are a specialty item because of the horizontal mounting and a special way they have to be sealed.

Good luck!

[Inland RV Center, In]

The "horizontal shock" as used by Airstream is made by Gabriel, which is stamped into the shock body.

Andy

[gklott]

Having to replace front curb tire with almost exact condition. Goodyear Marathon less than 1 year old. Apepars to be brake lockup damage. Working now to fix brake.

Cost $161 with mounting, balance,...

Sure caused lots of bad vibrations - noticed when lower door hinge pin always climbed out while traveling.

73/gus

[razorback]

This same thing happened to me today! I checked the tire pressure and lug nut torque on our 2005 Classic this morning before leaving. After traveling 426 miles, after I parked, I noticed one part of the tread on the Marathon worn all the way slick. After checking the lug torque (which all were fine) and the tire pressure (same as when I left this morning) I replaced the tire with the spare. After inspecting the tire it has severe wear for about 8", then normal tread until the opposite side where again there is the same 8" wear pattern. It is on both the inside and outside tread, leaving a faint tread pattern between the slick spots. The wear spots are exactly opposite on the tire. The tire affected is the front curbside tire. Could this be brake or axle problems? While driving I didn't noticed any braking shudder or anything that would indicate a problem. I thought I would replace the tire tomorrow and have them check the wheel to see if it is bent. If the wheel isn't the problem, I guess I'm looking a trip to the Jackson Center.

[Inland RV Center, In]

Originally Posted by razorback

This same thing happened to me today! I checked the tire pressure and lug nut torque on our 2005 Classic this morning before leaving. After traveling 426 miles, after I parked, I noticed one part of the tread on the Marathon worn all the way slick. After checking the lug torque (which all were fine) and the tire pressure (same as when I left this morning) I replaced the tire with the spare. After inspecting the tire it has severe wear for about 8", then normal tread until the opposite side where again there is the same 8" wear pattern. It is on both the inside and outside tread, leaving a faint tread pattern between the slick spots. The wear spots are exactly opposite on the tire. The tire affected is the front curbside tire. Could this be brake or axle problems? While driving I didn't noticed any braking shudder or anything that would indicate a problem. I thought I would replace the tire tomorrow and have them check the wheel to see if it is bent. If the wheel isn't the problem, I guess I'm looking a trip to the Jackson Center.

Balance, balance, balance.

The reason your tires are wearing uneven, is lack of proper running gear balance. That wear can happen very quickly.

Not just the tire and wheel, but the complete assembly that rotates, must be balanced.

Andy

[Ganglin]

Can I just vent a second on this issue. I have $600 in new tires, plus the new wheels that Andy recommended, and new shocks in the garage ready to go on the trailer. They have been lug centric balanced.

I'd love to have the entire hub assembly balanced the way Andy recommends but - when I've tried to find someone to do it they look at me like I'm an alien. Has anyone found anyone outside Inland that will do this procedure? The current tires are even on the curbside - the streetside are both cupped on the outer tire edge only.

[razorback]

Thanks, Andy. We are about 270 miles N of Jackson Center so I guess we'll just call them and mosey on down there. I guess they should be able to balance it. Thanks for your information.

R

[Inland RV Center, In]

Originally Posted by Ganglin

Can I just vent a second on this issue. I have $600 in new tires, plus the new wheels that Andy recommended, and new shocks in the garage ready to go on the trailer. They have been lug centric balanced.

I'd love to have the entire hub assembly balanced the way Andy recommends but - when I've tried to find someone to do it they look at me like I'm an alien. Has anyone found anyone outside Inland that will do this procedure? The current tires are even on the curbside - the streetside are both cupped on the outer tire edge only.

Many truck tire centers can do that balancing.

Andy

[Ganglin]

Thanks Andrew. I'll try giving a few a call.

[Airstream25]

daydreamer
Your links did not work for me, so I could not view your pictures.
You may have a brakes problem.

I had a similar occurrance that came to my attention via a blowout.

Later investigation revealed that two wheels had leaking grease seals making the brakes much less effective on these wheels. The two good wheels were essentially doing all the braking work and were locking up the wheels causing the worn flat spots. I am guessing the majority of the wear occurred during one hard stop when a highway traffic light turned yellow as I was very near the intersection.

As a test to see if this could be your problem, find a dirt road with no traffic and intentionally make a stop from about 5 mph using only your trailer brakes with the controller set to a strong value.

Get out and look to see if all four wheels have locked up as evidenced by a little pile of dirt pushed in front of each tire.

What you might see is some wheels do not lock up while others are doing most of the braking work.

If all four wheels locked up OK, then your brakes may be OK and then you could consider other causes such as balance or alignment.

Originally Posted by daydreamer36535

Hi all,
in preparation for a trip I was checking the tires out and have found
a problem i'm confused/concerned about.
see pic at http://www.gulftel.com/3strong/tire1.jpg
http://www.gulftel.com/3strong/tire.jpg

This is on a 1974 ambassador, 29'.
So, dual axle and the problem is on one side only.
I see no loose bolts ect.
also it seems this problem occured within the last 1000 miles as I just checked the tire pressure before coming home on the last trip.
As you look at the tire, there is deep wear for 2-3" then all is well
for about 6" - 16" then another deep wear pattern, all around the
tire. This occured on both tires. Its almost like the tire is trying to become square in spots.


What could be the cause?
thanks
Joe