Trailer alignment

[Jefff929]

I have been having a problem for as long as we have owned our 5er, excessive tire wear on the inside of both rear tires. I took the trailer in to an alignment place today. The rear tires had much (way under stated) negative camber and a bit much toe-out, the fronts also had ~3* negative camber and toe-out.



The tech didn't even bother with checking the rear, he just started adjusting. Until he got it close enough to bother measuring, there was no point to even know how far out they were. You could see with your eyeball there was an issue.



I'm suspicious that the trailer was either in an accident, from the previous owner or shipped that way from the factory. The tech said it looked like the right side had been in a hole and that it is not uncommon for trailers to need a little adjustment even new.



Now I have a new mission, to see if the alignment changes MPG or tire change interval due to wear. I haven't been getting poor towing mileage, but who knows. On average we have been replacing the rear tires about every 3-4,000 miles. At first I thought it was because of the age of the tires, or they were the cheap Chinese ones, now I'm not so sure. If I get to wear the face of the tread down a little that will be the thing that seals the deal and will make me a believer in trailer alignment.



Wish me luck, we have a trip coming up to the Oregon sunstone collection area located ~25miles NE of Plush, OR. The road to the sunstone mines is 25 miles of washboard. Weird, in WY the washboard tended to be at the turns and stops, this whole freaking road is a washboard. I guess this will test the alignment. :-laf

 

[SSell]

Interested to see if that helps---I havn't been able to keep a set of ST tires running long enough to check for wear patterns

 

[Grizzly]

What your problem sounds like to me is that someone flipped the axles on your 5er and didn't keep them crown up.
In other words I'm thinking that your axles are pre cambered.
If you look at the axles under the trailer and see that they are bowing down in the middle, they are pre cambered, which means that they can not be realigned to bend the opposite direction.
If this the case, you will need new axles and have it done be someone that specializes in trailers, not wheel alignment shops.

 

[HBarlow]

Your signature doesn't list the make and model of your trailer so it's hard to offer any useful information.



The misalignment you described seems to be fairly common. I notice it occasionally when following behind some trailers.



It is most likely to occur with some of the less expensive brands of trailer which use Communist Chinese suspension components.



The suspension is underrated for the load or, perhaps not capable of truly supporting the load they are rated to carry, and normal travel, accentuated by a high crowned roadway, bends the outside ends of the axle tubes.



You may want to determine where your suspension components were manufactured and what the rated capacity of axles and springs is.

 

[Jefff929]

What your problem sounds like to me is that someone flipped the axles on your 5er and didn't keep them crown up. In other words I'm thinking that your axles are pre cambered. If you look at the axles under the trailer and see that they are bowing down in the middle, they are pre cambered, which means that they can not be realigned to bend the opposite direction. If this the case, you will need new axles and have it done be someone that specializes in trailers, not wheel alignment shops.

I took it to a trailer shop first, they sent me to the shop I went to today. The place does it all big trucks, RVs and cars.

They are the best by far, I wouldn't trust someone else to do this kind of work. I had issues with my truck from the time it was new, and the dealer and the wheel & tire alignment shop's answer was to rotate my tries to mask the wear. After this place aligned it I have gone through 2 sets of tires and the only reason I have rotated tires was to keep them from rounding on the front and squaring on the rear.



It is entirely possible the axles were flipped by a previous owner, IDK. The rear axle looked bent well beyond any pre camber that anyone would have if they were only flipped. When the tech guy showed me what he could see with his equipment it was really obvious that someone had backed into something hard on the right side or it was bent prior to install at the factory. I can believe, after seeing over 100 problems documented on a friends special order RV trailer, that it may have been done in assembly or assembled by folks who just didn't give a #### about the job they were doing. I really prefer to believe that it was a backing accident, rather than going to the dark place thank you.

 

[Jefff929]

The misalignment you described seems to be fairly common. I notice it occasionally when following behind some trailers.

I agree

It is most likely to occur with some of the less expensive brands of trailer which use Communist Chinese suspension components.

Oh god, I hope not.



The trailer place I took it to first has been in the utility trailer fab and upgrade business a long time, friend of a friend, and only just learned of this practice in the RV industry. But I don't know why it would surprise anyone that this is going on now days.

 

[jelag]

Some axles have a bend in the center so that when the weight is on the springs the wheels are straight...

When you do an alignment on a car, the CAMBER, the inward or outward tilt of the kingpin at the top is measured with a very accurate level... negative camber is in at the top... I wouldn't accept 3* negative camber and would accept nothing but zero toe.

Toe is built into a front end to allow for compression of the tie rod ends when under speed... . if the tie rods are behind the tires then there is toe in. . and compression of the joints bring the toe to zero...

I've taken a 36" level to trailer wheels setting the level against the tire at the top and bottom making sure that the level doesn't touch any of the lettering... . I'd expect the bubble to be dead center.

Hope this helps...
If I had a problem with my trailer I'd tie down the axle and bend it with a port-a-power or 50 T hydraulic jack...

 

[Grizzly]

Some axles have a bend in the center so that when the weight is on the springs the wheels are straight...



If I had a problem with my trailer I'd tie down the axle and bend it with a port-a-power or 50 T hydraulic jack...

Jim, that's called pre cambered. Tying the axel and bending with a hydraulic jack won't fix the problem. The axels will only get deformed within 200 miles after they have been aligned. The only thing you can do is install new pre cambered axels. It is true that when you place the weight of the trailer on pre cambered axels, the axles will look straight.

 

[HBarlow]

Complete new American made axle assemblies with brakes and springs are not very expensive if anyone decides to replace inadequate suspension. SouthWest Wheel is just one of many sources for trailer components. SWW has a good website with prices and descriptions.



SWW will build custom made torsion axle setups for trailers on request. After towing Airstreams with torsion axles for years I bought a very nice Avion that had old fashioned springs. I priced a pair of complete torsion axles at SWW complete with new brakes, etc. With parts and labor, the installed price was only $1500.

 

[Grizzly]

Jeff. did you get the problem resolved?

 

[Jefff929]

Thanks for asking. As far as I can tell, yes.



I have spent the last week getting parts from the brown truck and installing them. Mostly little things, like the refer roof vent that caught a tree limb. So the trailer hasn't moved since I brought it home from the shop.



One thing that is really noticeable, the wife even mentioned it, is the rear tires and wheels no longer look like a female dog trying to do business. :-laf



The proof will be after our trip at the end of August. If, like one poster said it reverts after 200 miles, it will do it on that road.

 

[jelag]

Grizzly... . thanks for the right term "pre cambered axle"..... I had no clue what the correct term was...

However I have had luck bending axles, just like you'd bend the I-beam axle of a truck... . I've had to do it twice in 30 some off years... . but both of those were not the above mentioned axles...

I did have a pre cambered axle twist on me... . the tack welds broke and when the brakes were applied hard I had it twist... I just loosened the u-bolts, twisted the axle back with a big pipe wrench and a cheater. . re-welded it and its still working today...

 

[Grizzly]

Grizzly... . thanks for the right term "pre cambered axle"..... I had no clue what the correct term was...



However I have had luck bending axles, just like you'd bend the I-beam axle of a truck... . I've had to do it twice in 30 some off years... . but both of those were not the above mentioned axles...



I did have a pre cambered axle twist on me... . the tack welds broke and when the brakes were applied hard I had it twist... I just loosened the u-bolts, twisted the axle back with a big pipe wrench and a cheater. . re-welded it and its still working today...

Jim, I had no luck with bending the axles on my, then 88 Holiday Rambler 29' 5er. When I purchased my 95 Dodge/Cummins 4WD in 95, the truck was too tall for the trailer. I took the 5er to a trusted RV shop near my house to flip the axles under the the leaf springs. They did that, but they turned the axles 180* so that the axles were bowing with a downward arc. So they bent the axles to straighten then out. I didn't know they had bent the axles until a few weeks later in Fairbanks, Alaska. I kept noticing that the inside of all 4 tires were wearing and that the axles were showing a downward arc. I had the axles realigned (bend) in Fairbanks. By the time we got to Anchorage they were getting that downward arc again. I had all 4 tires removed from the rims and turned 180* and remounted on the rims so I could wear the other side of the tires. Some weeks later on the way home one axle broke from all the bending. In 100 Mile House, BC, we were down for a few days waiting for a new axle. With a new axle, with the arc upward, we got to Portland, Oregon where we purchased two new tires for the new axle and we put the two spares on the bad axle. As soon as we got home after two months of traveling, I took the 5er back to the RV shop. The realized what they had done wrong and without hesitation, they replaced the other axle, complete with new brakes drums, bearing, shoes, all bushings and other hardware at no charge and reimbursed for the first axle.



What we all learned by this experience was that one can not bend a pre cambered axle and have it stay bent. Another lesson learned is that when making a trip to Alaska, take two spares for the 5er. Out last trip to Alaska was two years ago with a Lance Camper.

 

[Road Dog]

I took the 5er to a trusted RV shop near my house to flip the axles under the the leaf springs. They did that, but they turned the axles 180* so that the axles were bowing with a downward arc. So they bent the axles to straighten then out.

That's just retarded. It might have worked in the '70s with straight tube axles. Modern axles often have spring perches top and bottom for spring over/under mounts and if not you buy some spring perches and weld them on.

 

[Grizzly]

That's just retarded. It might have worked in the '70s with straight tube axles. Modern axles often have spring perches top and bottom for spring over/under mounts and if not you buy some spring perches and weld them on.

Tell me about it!

 

[hilda]

If you see an axle with dual perches that trailer has had the axles flipped properly. When we flip the axles we add a perch to the top side.





The majority of trailers that we ship out are pre cambered (Axles bent up). I have never seen a trailer from the factory with dual perches, I wish they would it would save a lot of shop time.



If your axles are bent down in the center, you need to flip the axles over and have perches welded to the top side.



Jim

 

[Grizzly]

If you see an axle with dual perches that trailer has had the axles flipped properly. When we flip the axles we add a perch to the top side.

The majority of trailers that we ship out are pre cambered (Axles bent up). I have never seen a trailer from the factory with dual perches, I wish they would it would save a lot of shop time.

If your axles are bent down in the center, you need to flip the axles over and have perches welded to the top side.

Jim

Exactly correct, you want the axles straight or with a slight upward arc.

 

[Jefff929]

Jeff. did you get the problem resolved?

Well, the alignment held. There is a noticeable arc now in the axles that wasn't there before. The trailer performed well and I saw after many miles on washboard roads that the tires are wearing on the faces rather than the sidewalls.



I did have one casualty.



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The tire store in Lakeview OR said the roads out there give them decent business in the summer. :-laf