Fix for tire wear and positive camber

[Johnny M]

We installed new tires on our '71 Boler this past year with what I believe is the original axle with no obvious signs of damage to the axle but we noticed that when looking at the tires at a distance from behind the trailer and on level ground the tires lean in toward each other at the top. The unit is not overloaded and I can feel some unusual "stepped" tread wear by feel on the tires and we have very few miles on them, probably less than 2K. While searching I found this photo on flicker and wondered if this is normal for Bolers and Scamps, mine is the opposite of the lower left image from the photo but knowing the axle was installed with a leading arm configuration (wheels forward instead of wheels backwards) this makes sense that mine tilt in instead of out. From looking at this picture it makes me think this is standard for this type of axle. Anyone else have this issue?

[The Minimalist]

I'm not a Boler owner, but I know a few things about axles.

If that is the original axle on your '71, most likely you are seeing the result of 45 years of wear. When the axle is made, leading or trailing arm, it will be built with positive camber. The camber can be reduced by a number of things; bent axle, bent spindles or worn internal parts.

I'm thinking that the rubber torsion components of that 45 year old axle have seen their useful life and are compressed upward on the outer end of the axle tube, giving you a negative camber. Your only option in this instance is to replace the axle.

You may want to find out from some Boler owners who have replaced axles how much higher their trailers rode after the exchange. I'm thinking that your wheels are pretty far up in the wheel wells.

[Johnny M]

Thanks for the reply Clif...is there any reason why I should stay with a rubber torsion axle as opposed to one with leaf springs?

Also if it was a trailing arm installed as a leading arm or vice versa would that make the wheel tilt in the opposite direction or does that not matter?

[Donna D.]

Originally Posted by Johnny M

Thanks for the reply Clif...is there any reason why I should stay with a rubber torsion axle as opposed to one with leaf springs?

I'm not Clif, but leaf springs mean you'll need shock absorbers too. That means metal fabrication. Remember these trailers are like rolling earthquakes going down the road. A torsion axle has the dampening built in, with the rubber torsion.

[Jon in AZ]

Really don't know much about it, but I'm wondering if the frame cutout for the drop floor at the door will create problems with spring mounting points on that side.

As to leading versus trailing, up is still up, so positive camber isn't affected.

[Johnny M]

Originally Posted by Donna D.

I'm not Clif, but leaf springs mean you'll need shock absorbers too. That means metal fabrication. Remember these trailers are like rolling earthquakes going down the road. A torsion axle has the dampening built in, with the rubber torsion.

Thanks Donna for the reply but you can have a leaf spring axle without them although it might be a rougher ride...

http://rsleafspring.com/images/Ident...s%20IG%201.gif

[Jon in AZ]

Why would you settle for a rougher ride? I'd want the smoothest ride possible for a travel trailer. Easier on the trailer and all its contents. Unlike a cargo trailer, where the final loaded weight can vary greatly, the loaded weight of a travel trailer can be anticipated fairly closely and the axle tuned for the load.

[Johnny M]

Originally Posted by Jon in AZ

Really don't know much about it, but I'm wondering if the frame cutout for the drop floor at the door will create problems with spring mounting points on that side.

As to leading versus trailing, up is still up, so positive camber isn't affected.

If you inverted the entire axle 180 from front to back instead was my thinking on reversing the camber...as far as the rougher ride I agree I would not want a rougher ride just clarifying that you don't have to have shock absorbers with a leave spring axle, many stick built trailers don't have them

Oh and yes the drop floor might post a problem but I thought about elevating the ground clearance to accomdate

[Johnny M]

One of my reasons for the straight axle with leaf springs vs the torsion axle is the rubber torsion seams to be a weaker design to me and more prone to wear particularly of the rubber component.

[The Minimalist]

Generally speaking, I think you will get a better ride with a small trailer by going with the torsion axle. Several folks have recently gone to leaf springs from torsion axle and have commented on how bouncy the trailer is now. It's a bit of an exaggeration, but it's as if a torsion axle had shock absorbers. The rubber torsion elements respond differently to compression than leaf springs.

[floyd]

Originally Posted by Johnny M

One of my reasons for the straight axle with leaf springs vs the torsion axle is the rubber torsion seams to be a weaker design to me and more prone to wear particularly of the rubber component.

You have one which lasted 45years and you are concerned about strength and wear??

[Jon in AZ]

Originally Posted by The Minimalist

Generally speaking, I think you will get a better ride with a small trailer by going with the torsion axle. Several folks have recently gone to leaf springs from torsion axle and have commented on how bouncy the trailer is now. It's a bit of an exaggeration, but it's as if a torsion axle had shock absorbers. The rubber torsion elements respond differently to compression than leaf springs.

Not just small trailers. Doesn't Airstream use rubber torsion axles?

[Donna D.]

Man, I was thinking the same thing Floyd. There's an old saying, just because you can doesn't mean you should. Yes, stick built trailers sometimes have leaf springs... we know what those used trailers sell for. Leaf springs are cheaper to install and replace. If you're good with tools you can replace an axle in the driveway. Can do the same thing with a torsion axle if bolting to a bracket.


Both of my trailers have torsion axles. Heck, the 5.0TA has two torsion axles AND springs.

[Jon in AZ]

Judging by the number of pieces of broken trailer springs I have found at backcountry campgrounds, I don't think they are immortal, either.

This forum discussion has some helpful comments about the advantages and disadvantages of both: Leaf Spring vs. Torsion Axles. It's in the context of larger trailers and fifth wheels.

Here's more of a beginner's article: Leaf Spring Axles versus Torsion Axles

[sokhapkin]

Originally Posted by Donna D.

Heck, the 5.0TA has two torsion axles AND springs.

Which springs? Why?

[Johnny M]

Jon, Floyd and Donna you all make very good arguments and I guess 45 years is not too bad lol, I guess when I learned about the torsion axle over the last year or so and the post here about issues I got it in my mind that the rubber wasn't as durable as other types of axles...Jon I did not know Airstream used them too. I do like Donna's idea though of a bolt on torsion axle as I really don't want to cut & weld on my frame to remove and install a new one as the frame is in good shape.

And yes like sokhapkin said what springs?

[Johnny M]

Regarding the picture of the wheels tilting outwards, can this happen with a new one say from being under loaded? Is there an adjustment such as shimming the axle at the frame to correct this?

[Byron Kinnaman]

It seems to me that switching out a rubber torsion axle for leaf springs/straight axle in like switching out your cell/smart phone a land line rotary dial phone.

[Donna D.]

Originally Posted by sokhapkin

Which springs? Why?

It has springs because leaf springs are adjustable at the shackles. ETI is building 5.0TAs for many different pickups and it seems each truck manufacturer has a different bed height. I know my 4x4 Ford is a different height than a 2x4 Ford of the same model.

[Johnny M]

Browsing here for axle information regarding Bolers & Scamps I found this Boler in which the owner replaced the torsion axle with a leaf spring type without shock absorbers. http://www.fiberglassrv.com/forums/i...34290/5674.jpg

Anyone here got a rubber torsion axle replaced on their Boler recently and if so what did you install and what was the cost of the axle by itself and the cost to have it installed.

I really don't want to pull the body off the frame again but I am concerned about someone burning my new wood subfloor or even worse the fiberglass during the process of cutting the old axle out and welding in a new one, (not to mention the possibility of damaging or weakening the frame)...read a post here about that happening to another Boler owner. I considered tackling it myself since I could take my time an exercise a lot more caution to prevent that from happening as opposed to someone trying to get mine in and out quickly for the next one in line...

Also another thought was the flammability of the rubber undercoating I sprayed on the subfloor, the flexible spray on rubber coating in a can stuff. I would hate to see all my hard work go "poof"