trailer wheel alignment

[bigjimg]

Gidday all
I've noticed that the front wheels on the dual axle trailer are scrubbing out the inside tread pattern significantly.All pressures are good only doing it on the front axle.The question is can the wheels be aligned so as to track straight?I know how things happen when turning etc etc but this is excessive.Didn't happen on my 8 by 5 tandem box trailer,and it carried a load of around 1.2 tonne constantly.If anyone knows of a place that could carry out such work let me know.Thanks.Jim

[Kleyny]

easy to check it yourself with a straight rule. Put it up against both tyres and see if there is a gap.

What sort of tyres are you running?

neil

[bigjimg]

Gidday Neil
Mate they are a dunbier tyre 175/80 13inch rim.Already had the 2m straight edge across the side walls and no misalignment there.It looks more like a camber issue,but who knows if that can be,lets say," manipulated".It could be that the tyres are just cheap sh#t made in China rubbish.If it turns out that is the case i'll rip the beggers off.Otherwise could get expensive.These tyres would not have done more than a couple of hundred Ks,and showing signs of serious wear.Jim

[tunaticer]

Most likely it is because your rear axle is taking more weight than the front axle letting the front tyres scrub whilst cornering esp. at low speeds and tight corners. Unfortunately with tandem axles and uneven weights on each axle it is a fact of life you will have to live with. Even with perfect wheel alignment the problem will still exist.
Are the centres of the axles fairly close together or spaced a fair amount apart?
The closer they are together the less the scrubbing will be.

A tandem box trailer will nearly always load evenly due to its short load bearing nature. A boat trailer has a lot more off centre of the load area factors in its design.

Using a straight edge to check alignment only checks the wheels are in line with each other, it does NOT check to see if the axles are square to the trailer hitch. To check this you need an accurate measurement from the hitch to the front of each end of the axle. If those two measurements are exactly the same then it is in line with the towing hitch. 5mm difference will see all tyres scrubbing out quickly as the trailer will slightly crab its way behind the tow vehicle.
The second axle should measure identically either side back from the front axle that has been squared to the tow hitch. Any other method is plainly bullshit.

[Kleyny]

Good point Jack.
Jim said that it only the front tyres scrubbing and both axles are parallel. So that rules out both of our guesses.

You can check your camber by using a square or bubble guage. Not real accurate but enough to tell if its scrubbing because of the camber with very little ks as stated.

I didn't know Dunbier made tyres. But at a guess they have probably got a cheap tyre manufacturer to stamp there name in the side.

You could always take your tyre down to a few reputable tyre joints and see what they say. I know some will tell you there cheap crap just to sell you there brand. But hopefully you can find a decent guy that will tel you straight.

neil

[bigjimg]

Thanks for that fellas.What i will do tomorrow is set up the laser and strike a centre line to the tow hitch and rear of trailer.Then set up the laser across the width and check the centre of each axle.I will let you know the outcome.Thanks for that.Jim

[White Pointer]

G'day,

When you are measuring trailer axle alignment, measure from towball coupling centre to trailer front axle centre. Then measure trailer front to rear at the axle centres, not the tyres.

Also check the height of the centreline of the towball on the trailering vehicle with the centreline of the back axle of the vehicle and the axles of the trailer. Do this with usual vehicle and trailering load.

This is because if you put lots of weight in the towing vehicle and it drops the suspension it will pull the towball down and make the forward trailer axle a pivot.

The solution may be as simple as having a number of towbar inserts to keep the trailer level, depending on loading.

White Pointer

[cormorant]

You can use tow ball height to " ëven " out trailer so it rides parallel and it may force more even weight on each tyre.

Front axels cop all the gutters etc so are often bent or bend spring mounts etc so have a look at the mounts as well.

As others have said measue=re up and make sure alex is equidistant from ball and second axel also

[1lastcast]

Hi Jim i can help you with your trailer ........ pm sent

regards Peter

[walruss]

Jim I assume you mean its a dunbier trailer. I had a similar problem with a dual axle trailer with wear on the inside of the tyres. i took it back to the factory. It was a camber issue. They "adjusted the axle" read rebent the thing witha forklift, gave me two new tyres and rims, so all was good, and never had a problem from then on. it appears that the axle had a mild bend in it from day 1.

Check your axle for straightness. maybe the problem.

Russ

[Noha]

yep a slightly bent axle will do that every time.
try rotating the axle 180 degress.

[bigjimg]

Jim I assume you mean its a dunbier trailer. I had a similar problem with a dual axle trailer with wear on the inside of the tyres. i took it back to the factory. It was a camber issue. They "adjusted the axle" read rebent the thing witha forklift, gave me two new tyres and rims, so all was good, and never had a problem from then on. it appears that the axle had a mild bend in it from day 1.

Check your axle for straightness. maybe the problem.

Russ
Gidday Russ
New June last year.Pretty hopeless At setting up trailers in my opinion.This is just another in a series of things.If you want something done properly you do it yourself.Jim

[dogsbody]

Anything come of the laser guided injection measurer thingy dohicky?

Dave

[walruss]

Jim, while the trailer may have problems, the setup is the dealers responsibilty, not the manufacturers. I agree with the frustration though.

I bought a secondhand boat where the trailer setup was crap. the trailer is good, it was just that the setup by the dealers (QLD dealer, something do with sunsets) was so bad the hull hit the crossmembers.

Took many hours to fix the problem.

Russ

[bigjimg]

Anything come of the laser guided injection measurer thingy dohicky?

Dave
Okay
These are the results of the axle alignment on my trailer as follows.

Starboard Front axle from square 495mm
Rear 1213mm
Port Front 491mm
Rear 1210mm
As you can see not much in it but probably enough to cause abnormal wear.Jim:-[