Does anyone know if horse trailer axles have to be aligned any different than any other vehicle? For those that have knowledge in this area, I know this sounds stupid. But, my trailer tires separated at 12 months. The shop said the rear axle was out of alignment. They performed an alignment. Replaced the tires. Now, 12 months later, I have tire separation on the rear tires AGAIN! Sounds like they did not perform a proper and complete alignment. Any ideas?
Posted 2006-12-16 10:55 PM (#52555 - in reply to #52553) Subject: RE: Axle Alignment
Expert
Posts: 2953 Location: North Carolina
I would ask some more about why they think an alignment would cause "separation" I'm assuming you mean when the tread separates from the tire carcass. I would think an improper alignment would wear out the tread. Seems like your tires are failing from improper inflation or overloading. Something that would create heat in the tire and cause the tire ply bond to fail.
Posted 2006-12-17 6:51 AM (#52559 - in reply to #52553) Subject: RE: Axle Alignment
Member
Posts: 14
Location: hartford city, in
Most trailer axles are welded in place and there is no way to realign without cutting off and rewelding. Dont know what your trailer has but it does sound more like overloaded tires to me.
Posted 2006-12-17 7:30 AM (#52563 - in reply to #52553) Subject: RE: Axle Alignment
Member
Posts: 43 Location: Valdosta, GA
Thanks for the advice, but unfortunately overloading and inflation is not the cause. The new tires are G rated and have a load capacity (all 4 combined) of 15,000 lbs. I check inflation before and during EVERY trip and I never travel faster than 67 mph.
As for the axles, mine have bolts that allow for small adjustments. That's how they adjusted the alignment last year.
Posted 2006-12-17 2:49 PM (#52577 - in reply to #52553) Subject: RE: Axle Alignment
Member
Posts: 14
Location: hartford city, in
A quick way to check the alignment yourself is to drop a plumb bob off of the coupler to the ground and make a mark on the ground. Do this also off of the wheel bearing caps, front and rear both sides. The measurements should be the same from the front axle to the rear axle, and from the coupler to the front axle on each side and the coupler to the rear on each side.
Posted 2006-12-17 8:11 PM (#52586 - in reply to #52553) Subject: RE: Axle Alignment
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Posts: 2689
For which trailer ?
I can talk in generalities, but not all trailers are created equal(ly).
Alignment can and should be checked as someone else outlined, by dropping plumb lines from the coupler and - Ahhh this is the HARD part, finding the real center of a hub or grease cap. Anyway, do it on a flat level surface, etc and I think the usual tolerance is only about 1/8 or 1/4, so chalk doesn't work very well. You might get better accuracy by just getting under there and measuring from front axle surface of front axle to front axle surface of rear axle - as far out (close to the wheel) as you can. This will at least tell you if they're parallel.
SOME axles, e.g. Dexter Air-Flex, are adjustable - at least the rear one is adjustable to get it parallel with the front one.
All this aside, I would expect excessive WEAR from misalignment, not tread separation.
BTW, are these ST tires ?
and are you inflating them to their MAXIMUM cold load rated pressure ?
I'm a bit curious that your tire guy told you specifically that the REAR axle needed alignment - it could indicate that he knows that it CAN be aligned.
Posted 2006-12-18 7:58 AM (#52595 - in reply to #52587) Subject: RE: Axle Alignment
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Posts: 2689
Originally written by Pleasure Man on 2006-12-17 9:06 PM
Thanks Reg,
The trailer is an 04 Kiefer 10' SW 3 horse. All alum. and 8'6" wide. It has Dexter axles.
The tires are ST tires and I always keep them at the max. cold psi.
Later this week I am going to get to an alignment shop and have them check the alignment. I will check using your method.
I don't know the Keifers well enough to comment specifically on whether they weld everything in place or bolt up the Dexter components and leave allowance for adjustment.
Just a couple of things;
I think ST tires are usually rated for 65 MPH.
I guess that comment will bring a shower of replies from people who claim to drive on them at speeds way over 65 "all the time" with no ill effects.
Max cold inflation pressure is only appropriate for max load, but you probably know that already. I hold a belief that inappropriately hard tires will ride harshly, skip and scuff - many disagree with me, see other posts on this.
You can't always multiply the rating on one tire by four and assume that everything will be OK just because that number is 80 or so percent of your trailer's total weight. If the truck is high (geometrically, not drug induced) you COULD have more load on the rear tires than the front ones.
A way of checking this is to feel your tires after an hour or two on the highway, if the rear one is detectably warmer than the front one on the same side then you probably have too much load on the rear axle.
If you can get to a weigh bridge you can get the answer to this quickly, have them give you a reading for each axle with the trailer loaded the way you normally load it. You'll probably have to do the arithmetic, but they can tell you the weight as each axle comes onto the scale - 4 readings.
Sand and gravel yards around here will often do it for $10 or free.
Posted 2006-12-18 10:19 AM (#52600 - in reply to #52553) Subject: RE: Axle Alignment
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Posts: 1283 Location: Home of Wild Turkey Whiskey
What year/brand truck are you pulling it with? 2 wheel drive or 4? Having owned a couple of KB trailers they don't raise the bed area on the trailers so they are usually running "uphill" with newer trucks, unless you have an older truck this may be your problem. As Reg has suggested get your axle weights at a feed store or gravel yard to determine if your rear axle weight is a little Higher. That is probley the problem.
Posted 2006-12-18 11:42 AM (#52603 - in reply to #52600) Subject: RE: Axle Alignment
Member
Posts: 43 Location: Valdosta, GA
My truck is an 01 F350 2wd. When I bought the trailer, I adjusted the coupler so that the front of the trailer box is app. 1" higher than the front of the front tire fender. My dealer said that this is the proper procedure for "leveling" the trailer so that the axles will be ok. So, it is basically a level trailer when hooked to the truck. Keep the ideas and suggestions coming, you guys are great!
Axle Alignment
