Well fellow ExploreOz members, Bushtracker Owners Group, I thought that it was time to give you an update to the Cracking ARB rear tyre carrier come tow bar.
This is written for the information of visitors and members. If you have an ARB rear tyre carrier fitted you need to be aware that there could be an issue if you use a non standard ball mount ie; Treg or AT35 in conjunction with Hayman Reese Weight Distributing Hitch.
Now, I am not writing this to bag ARB because I am of the opinion that they make an excellent product! But to make people aware that they could have an issue with their warranty.
I was advised that ARB had not conducted any stress tests but had made calculations by information I had supplied, measurements and weights of the caravan.
This is a reproduction of the correspondence that I received from ARB
Engineering have made some calculations based on simple linear measurements. Whilst these figures do not provide stress details on the various parts of the RSTB, they do give a clear understanding of why the failure has occurred.
• For every 10mm increase in the distance of the fulcrum point from the bar, represents a reduction to the standard 350kg ball loading of 3.3%
• In this case the pin (fulcrum point) is approximately 200mm to the rear of the centre point of the tow ball in the standard ball mount.
• 20cm x 3.3% = approx. 66% reduction in the ball weight capacity.
• In other words the maximum ball weight for this set up would be approx 120kg.
• His Bushtracker van has a tare of 2610kg and an ATM of 3500kg.
• Normally the ball weight should be approximately 10% of the mass ie: between 260kg and 350kg
• The designed maximum ball weight for this bar is 350kg. the setup as being used equates to a ball weight between 430kg and 580kg
The reason for the failure is clearly due to the extra leverage cause by the non standard ball mount setup. This product has been fit for the purpose for which it was designed and has not failed as a result of design or manufacturing defect, but as a result of misuse. It is therefore not covered under the terms of the products warranty.
Signed;
Roger Chestney
National Customer Service Coordinator.
Therefore their product was not at fault, no warranty claim.
ARB removed, striped the old carrier and painted and refitted a new one at a cost of $1076.
I just wonder how many tyre carriers ARB have sold and clients using the same setup as I use and are unaware that they are voiding their warranty through no fault of their own, I say this because ARB did not supply any documentation as to what is recommended for their tow hitch. I make this comment because I am not an engineer and believed I was using the equipment purchased in good faith and this is the same with the Hayman Reese 750 Weight Distributing Hitch. The hitch comes supplied with a pre drilled hole in the shaft and no distance information regarding attaching to the hitch receiver.
Contact with ARB:
I was content with the outcome as it stood but what I was disappointed in was that no one contacted me to explain anything, or give an undertaking that ARB would supply instructions with the ARB rear tyre carrier so to avoid simular issues arising in the future.
Roger Chestney contacted me and the following e-mail was received.
Hi Erik,
We hope you are
well and that your refund cheque has arrived.
We said we would update you on what we were going to do to prevent the same issue happening to other customers.
We have taken on board your concern, and agree that most customers would not realise the consequences of using non-standard ball mounts.
To this end, an Engineering Change Notice has now been raised that will lead to a warning being added to all relevant Installation instructions on the use of non-standard ball mounts. A warning sticker is also to be produced that is to be attached to each rear bar during installation.
Thanking you for your input into this issue and for your patience during the process.
Regards
Roger Chestney
THANKS ARB THAT’S ALL I WANTED,
THANKS