Tyre wear on tandem trailers

Hey Jim · Guru

Tyre wear on tandem trailers

TechnoGypsy · Veteran Member

Howdy Jim - do you have a pic of the tyre wear pattern ?

These links may help =

http://grassrootsmotorsports.com/forum/grm/what-causes-trailer-tires-to-wear-like-this/43783/page1/

http://www.google.com.au/url?sa=t&rct=j&q=&esrc=s&source=web&cd=4&cad=rja&uact=8&ved=0CDEQFjAD&url=http%3A%2F%2Fwww.roadkingtrailers.com%2FTireWearChart.pdf&ei=yjqxVMvRAeGxmAW6h4HIDw&usg=AFQjCNE_mwwkFUqUR56pDr7ffVpqbI1x4w&sig2=WjaaI44G4wHhbuWiNfTzug&bvm=bv.83339334,d.dGY

http://www.etrailer.com/question-37871.html (this one mentions flipping the axle)

cheers from Technogypsy

Woody n Sue · Guru

Hey Jim what size are the tyres that number means nothing should have a figure like 185/65/15 for instance, there will also be a recommended tyre pressure on the tyre at max weight for that tyre size and ply rating, can't imagine why you would be running such high pressure in them should only be around 32 to 35 psi depending on the tyre size and ply rating this could be a part of your problem but it's most likely the the two axels are fighting each other in other words they are not parallel with each other measure very accurately each axel front to rear each side and see if the distance is the same if not this will indeed cause rapid wear of the tyres that you describe, does the trailer run to one side when towing ? If it is also measure from the tow hitch to the front axel u clamp it should measure the same to both sides so grab a tape measure on ya back and get under the trailer and see what you have .

Good luck

exa41 · Guru

Hi Jim , tyre wear can be attributed to a number of things,but it looks like the axles are under rated for the weight being carried. Bad tyre wear as you have is either excessive camber or toe out and both can be attributed to axles flexing under load , I doubt if the tyres are at fault.

Cupie · Guru

Quote ....

"do the caravans set up with tandem bogies suffer from tire wear/ bad camber like our boat trailer. Or are they engineered more up market"?

...................................................................................................................

To answer your question about tandem axle caravan tyre wear ...

I have traveled around 200,000 km in my old Jayco 21'6" Westport with dual axles & have never had any problem with uneven tyre wear.

I always replace my tyres due to age not wear. Usually at around 80,000 km after 5 or 6 years, with at least 20% of tread still left.

But then I travel at 80 to 90 km/hr with around 40psi (higher than Jayco specify) and only do short stages circa 300km/day on the blacktop. The Jayco has twin beam axles with independent load sharing leaf springs & weighs 2334 kg.

wasn_me · Guru

Most truck chassis, wheel alignment places will check your van, boat trailer for alignment.

Cheers Pete

-- Edited by wasn_me on Sunday 11th of January 2015 12:13:18 PM

Hey Jim · Guru

Hi Technogypsy & everyone else,

Thanks for your replies.Just to add to the ? The tyres are rated to 60psi max cold.So I don't think its the tyres themselfves.

I have replaced the springs and axels to original specs as well, a number of times.

I have measured the trailer to both centres before. But must do again, as I seem to remember moving the whole bogie back 100mm (by undoing the U bolts and attaching to a post (tel Pole) and pulling the trailer forward with the old tug sliding the frame forward 100mm.) to put more weight on the ball confuse confuse confuse The grey matter does not remember long ago.

The trailer has covered, probably 50,000km minium in its lifetime.

Could the camber in the road contribute to the cause as we have used the Barrier Hwy to Broken Hill many times.This Hwy is not kind to boat trailers with the shoulders, and we travel in the ruts caused by the heavy semies.

To me it seams that the axels are under rated.and sill bending/ flexing. they are 45mm x 45mm.

Don't give up on me just because I'm aging, just like the rest.

Regards Jim & Eunice

PS:The tyres cup on the inside only, as per Techo's first info ref:

From memory they never did this when the boat /trailer were new thats 20years back.when we traveled up and down the East Coast

-- Edited by Hey Jim on Sunday 11th of January 2015 04:59:50 PM

Baz421 · Guru

Hey Jim,, all is not lost.

I had a good run with Kenda tyres on tandem on boat trailer in the NT for 5 years or so, about 1200-1400 kg loaded. Ran to SA and lots of dirt as well. Never had a problem, very minimal wear.

It seems as if the problem is camber (assuming there is no "feathering" across the tread for toe out) and this could be a couple of reasons.

1st Axle - could be bent/flexing as you say, however 45x45 solid should take this load easily UNLESS you have bottomed out and given it a slight bend.

2nd. The trailer side rails could be flexing, but unlikely.

SUGGESTIONS.

1 Take wheels off and bolt a piece of STRAIGHT angle iron (as long as possible, to the wheel studs, inside the wheel arch, each side one axle at a time).

2 Measure each end of the angle iron in VERTICAL AND HORIZONTAL positions.

3 Look for difference in measurements, ie this checks toe out and more importantly any axle bend when angle iron is vertical.

4 Anything over 1mm difference would be an issue IMHO.

SOLUTIONS IF AXLE BENT

1 Straighten obviously

2 Turn axle over 180 degrees and see if the load bears down on it and straightens it when loaded (to do this chock the axle as close as possible to the brake backing plate/disc with FULL LOAD on trailer and remeasure using the vertical angle iron. You may not get full deflection of the axle as the tyres are not on the ground and the distance from the C/line of the tyre and the chock could be small and not have much influence..

I think you will find an answer here, well hopefully you will and at no cost initially.

This makes sense to me but sometimes my techo writing is confusing. PM me if you need clarification.

Cheers Baz

-- Edited by Baz421 on Sunday 11th of January 2015 10:42:10 PM

-- Edited by Baz421 on Sunday 11th of January 2015 10:49:57 PM

PeterD · Guru

Is Carter Westco a truck aligning firm or are they straightening the axles with no load on them. Caravan axles bend a little when you load them up. A lot of axles come with a little bend upwards in the middle so the wheels run true when loaded up.

Take your trailer with its usual travelling load on it to a truck aligner. I have never heard of anyone disappoint with their work. I used one on my previous van and my tyre wear problems were sorted.

Hey Jim · Guru

Hi Baz & Peter,

Thankyou both for your imputs.

Baz i'm still working for myself at the moment for another two years. Finding the time to sort out the problems will take time I don't have right now.I will take all that you have suggested into my computer bank and copy your responce on the printer, and do the task to solve the riddle.

Peter, Carter Wesco are custom builders of machinery trailers for local / State Govement / commercial as well as to the public.

When I took both axels to them,they set each axel up under the large press. then alined each in turn marking dead centre of each. Simply by placing a washer about 2mm thick on their marking, I watched this press come down on the washer and saw both ends of the axel bend by the same amount. They have done this for other clients as well.

Once I am happy with all measurements I will make shaw U bolts clamping the bogie to the trailer are fully tightened. If still a problem there after, I will check out the trucking alinement boys.

Regards Hey Jim

Aus-Kiwi · Guru

Seems a suspension geometry issue ? Tow out and too much camber... I have had solid axles on various trailers ..
Some to the eye the alignment wasn't perfect..
Tyre wear and tracking was Good.,
Never had tyre wear issues.. Should do 50,000 klmrs . Replacing them due to age etc

geometry and alignment is much more critical on IRS suspensions..

Much more changes in geometry in travel..

-- Edited by Aus-Kiwi on Thursday 22nd of January 2015 09:29:33 AM