by Tow Itch Sun 28 Apr 2013, 12:48 pm
Helen wrote:I asked regarding uneven tyre wear a couple of years ago ..... not on this forum, and the general thoughts were that the trailer was overloaded leading to the uneven tyre wear and taking weight off would alleviate the problem. This was obviously not the best advice I've been given as it turned out that the suspension arms were twisted although not really rusty so probably as advised overloading had caused it. No you can't see the twist until you take the units off and place them upside down on level ground when all is revealed ...... ours looked fine until we laid the plate on a flat surface.
Thank you for correcting me regarding overloading, as for saying check the suspension ..... I put a link to the advice sheet regarding what to look for when buying a used Dandy that Mike wrote, there are ways to check the suspension listed in it but what your saying is uneven tyre wear means you have to replace the suspension full stop.
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Not sure I've got some of what your saying the bit I'm talking about twisting is the trailing arm. the bit running from the pivot point to the stub axle.
No you can't see the twist until you take the units off and place them upside down on level ground when all is revealed ...... ours looked fine until we laid the plate on a flat surface.
If you are talking about a twist in the box structure that houses the pivot and the rubber then??? I have no idea.
but what your saying is uneven tyre wear means you have to replace the suspension full stop.
The simple answer is yes. The more exact answer is "yes and no and no and yes" (Copyright KAB 2008)
I'd imagine in almost every case you will have buggered the suspension but...
The Physics bit.
Steel if bent has an elastic and inelastic ability to bending forces.
If you take a steel rule and apply a small force the rule will when released flex back to it's original shape and produce a most pleasing twang if this action was performed upon a school desk. Go too far though and the rule is bent permanently.
[You must be registered and logged in to see this link.] Now the trailing arm isn't a flat bar of steel but I'm guessing that the square section tube that is the trailing arm could act as a torsional spring. (twisting motion)
So theoretically if you had a new suspension unit I'd guess you could get to a point of overload where the trailing arm could just begin to deform and removing the excess load would allow it to spring back.
In reality if is severe enough or long term enough to affect tyre wear I say it was almost certainly buggered.
Would I make the effort to strip the component to establish that the stub axle was or was not parallel to the pivot bar or would I just be replacing the units? I wouldn't see me wasting time with the former action.