Alko single axle problems

[Dustydog]

I inadvertently overloaded a 1000kg MTPLM caravan to 1240-50kg as weighed near Brecon during its first trip out. Needless to say the trip home was cautious, but fortunately I had fitted higher load index trailer specific tyres that were okay at the overload weight. On arrival home I got underneath and inspected the running gear and all was fine, no visual indication of a reduced gap between the tyre and caravan.
Intended to submit for Woosie membership on account of that faux pas.

🙀🙀Was that on your caravan that suffered the collapsed axle🙈

My TA at 1690kgs MTPLM , each axle is rated at 1000kgs, which imo gives a good margin, whilst stationary say😉
How was your single?

 

[ProfJohnL]

Do not forget that load is a force which is generated by the mass of the caravan times its acceleration, and when a caravan is in motion all the different accelerations the caravan experiences will cause the effect of that load to change. during some motions the accelerations will act in the same direction as gravity and thus the load applied through the axles and wheels will increase above the static load.

All vehicle and trailer engineers will be aware of this and the suspension products should be designed to accommodate these extra loads. The scale of the additional accelerations will depend on the speed of the outfit and on the quality of the surface over which its travelling.

Hard cornering will shift the direction of the effect of the caravans CoG and move more load onto outside wheel, abut towing over a bad pot hole or up a kerb at speed would likely put a pulse of high load through the system which could instantaneously more than double the static load on the side of the suspension and axle. These are load for which the chassis designer should know to take into account. the dynamic principles also apply to tyre load ratings and the tow ball on the car.

Consequently whilst an axle may have a maximum static load capacity of X whilst the system is stationary it should easily cope without damage if 2X load is applied. This is why its perfectly acceptable to use the caravan whilst your stopped at the services without unhitching it.

 

[otherclive]

🙀🙀Was that on your caravan that suffered the collapsed axle🙈

My TA at 1690kgs MTPLM , each axle is rated at 1000kgs, which imo gives a good margin, whilst stationary say😉
How was your single?

No it was on a Trigano 420 SD, a pop top compact caravan. I bought it after a three year gap after we sold our S5 Bordeaux and everything else in 2014. A case of heart over head, but a very good quality of build. From my inspection post overloading the rubber bushes we spot on.

 

[Buckman]

I shudder when I think that in the seventies the single axle caravan that we used was loaded with awning, suitcases, cases of beer etc and travelled on some of Africa's almost non existent roads and never gave us any hassles. However we had has lamps and probably no battery. The caravan never had a toilet. Three of us living in the caravan for up to 6 weeks at a time and no facilities for miles around. Not even water!

 

[otherclive]

A friend of mine in Australia has a pretty rugged caravan that they use for trips on challenging tracks, or no tracks. He tells me that trailing arm suspension with coil springs and shock absorbers is well regarded for reliability and performance. His has Alpha suspension an example shown below. Might just cope with British roads.

 

[Lutz]

A company approaches a supplier, and provides them with a particular specification for a component. If that supplier then fails to comply with that specification who is at fault? The customer, or the supplier?

Of course, if the supplier fails to comply with the manufacturer's specification the supplier will be at fault, but that's of no consequence to the end customer. The manufacturer still has final product liability, but if the specification is not met, he has opportunity for recourse action against the supplier.
I rather suspect, however, that caravan manufacturers often don't have comprehensive technical specifications of their own, but rely on those of the supplier and in some cases don't co-ordinate their requirements with the supplier adequately.

 

[ProfJohnL]

I would go further Lutz, For over twenty years I worked for a company that manufactured gas appliances some of which were supplied to the caravan industry. they were by far the most problematic customers.

During the caravan manufacturers development cycle we offered our advice to the manufacturers about which products would best meet their target market, only to find they would ignore our advice and make their own choices which sometimes were not even fully compatible with each other!

It also meant that we had to pick up the end users wrath and fix the caravan manufactures poor installation practices.

 

[RogerL]

I would go further Lutz, For over twenty years I worked for a company that manufactured gas appliances some of which were supplied to the caravan industry. they were by far the most problematic customers.

During the caravan manufacturers development cycle we offered our advice to the manufacturers about which products would best meet their target market, only to find they would ignore our advice and make their own choices which sometimes were not even fully compatible with each other!

It also meant that we had to pick up the end users wrath and fix the caravan manufactures poor installation practices.

That doesn't surprise me - caravan makers seem to disregard component manufacturers' installation guides - when our Lunar Clubman was delivered the poor heating performance was quickly identified as lack of air circulation, a fraction of that recommended by Alde - improved by dealer modifications but it shouldn't have been necessary.

 

[Buckman]

Of course, if the supplier fails to comply with the manufacturer's specification the supplier will be at fault, but that's of no consequence to the end customer. The manufacturer still has final product liability, but if the specification is not met, he has opportunity for recourse action against the supplier.
I rather suspect, however, that caravan manufacturers often don't have comprehensive technical specifications of their own, but rely on those of the supplier and in some cases don't co-ordinate their requirements with the supplier adequately.

If for instance a manufacturer of vehicles which could include caravans has certain parts made by a third party and a safety recall has to be issued, would the manufacturer of the vehicle have to bear the full cost of the replacement faulty part inclusive of labour or would the third party who manufactured the faulty part be equally responsible?

 

[Dustydog]

If for instance a manufacturer of vehicles which could include caravans has certain parts made by a third party and a safety recall has to be issued, would the manufacturer of the vehicle have to bear the full cost of the replacement faulty part inclusive of labour or would the third party who manufactured the faulty part be equally responsible?

The manufacturer takes the brunt and pays. Then he sues the TP. Where Proceedings have been issued against the manufacturer he will usually be advised to issue a Third Party Notice on the TP bringing him into the Proceedings. That action should not be prejudicial to the Plaintiff

 

[ProfJohnL]

If for instance a manufacturer of vehicles which could include caravans has certain parts made by a third party and a safety recall has to be issued, would the manufacturer of the vehicle have to bear the full cost of the replacement faulty part inclusive of labour or would the third party who manufactured the faulty part be equally responsible?

That depends on their contractual arrangements, and the end user has no legal interest in the arrangement.

 

[Buckman]

That depends on their contractual arrangements, and the end user has no legal interest in the arrangement.

I do not recall asking if the end user would have any legal interest as it is of no concern to the end user. However I did wonder if the one manufacturer would be able to claim some costs from the other manufacturer of the faulty part. It was just a general interest question.

 

[Lutz]

Dustydog has explained things quite well in post #35. Of course, the caravan manufacturer can claim against a supplier, but only if the supplier has failed to meet contractual agreements between the supplier and the manufacturer.

 

[otherclive]

I would hope that the long-standing relationships between caravan maker and parts suppliers are such that a commercial arrangement exists such that costs of defective parts are sorted out equitably without resort to law. That’s how good business should work.

 

[Lutz]

I would hope that the long-standing relationships between caravan maker and parts suppliers are such that a commercial arrangement exists such that costs of defective parts are sorted out equitably without resort to law. That’s how good business should work.

Such arrangements probably exist, but that doesn't help if there is disagreement as to what constitutes a defective part. Without an agreed detailed technical specification, the supplier may have different opinion than the manufacturer.
In the case in question, what if the manufacturer considers a 10 or 20% overload safety margin (to cover the odd possibility of towing the caravan for a specified number of miles on unsurfaced track or pave) to be normal if the supplier bases his design on less demanding conditions?

 

[otherclive]

Such arrangements probably exist, but that doesn't help if there is disagreement as to what constitutes a defective part. Without an agreed detailed technical specification, the supplier may have different opinion than the manufacturer.
In the case in question, what if the manufacturer considers a 10 or 20% overload safety margin (to cover the odd possibility of towing the caravan for a specified number of miles on unsurfaced track or pave) to be normal if the supplier bases his design on less demanding conditions?

I never said that the basis of the arrangements between maker and supplier should be without an agreed contractual specification; I would assume that to be a given. How else would the commercial arrangement that I mentioned be managed?

 

[Dustydog]

I told this before on here.
Decades ago an Italian Company supplied our client with plastic press fit valves for their gas boilers. The plastic valves when fitted fractured but didn’t completely break at first . After 18 months a high frequency of failures were noted in the field all resulting in explosions but fortunately not life threatening.
A very expensive Product Recall exercise was carried out involving numerous countryside gas engineers in the fitting of new reliable valves. Cost over £500k.
The Italians would only pay the original cost of the plastic, pennies.
It wasn’t worth the Legal cost of suing them.

The Prof has also listed a case he had with a caravan manufacturer.
Certainly not a bed of roses as you may think Clive. As the old saying goes “ There’s no friends in business” .
Remember the PPE outstanding fiasco🤮🤮

 

[ProfJohnL]

...
The Prof has also listed a case he had with a caravan manufacturer.
Certainly not a bed of roses as you may think Clive. As the old saying goes “ There’s no friends in business” .
Remember the PPE outstanding fiasco🤮🤮

Not a caravan manufacture but with a supplier of gas valves.

 

[otherclive]

I told this before on here.
Decades ago an Italian Company supplied our client with plastic press fit valves for their gas boilers. The plastic valves when fitted fractured but didn’t completely break at first . After 18 months a high frequency of failures were noted in the field all resulting in explosions but fortunately not life threatening.
A very expensive Product Recall exercise was carried out involving numerous countryside gas engineers in the fitting of new reliable valves. Cost over £500k.
The Italians would only pay the original cost of the plastic, pennies.
It wasn’t worth the Legal cost of suing them.

The Prof has also listed a case he had with a caravan manufacturer.
Certainly not a bed of roses as you may think Clive. As the old saying goes “ There’s no friends in business” .
Remember the PPE outstanding fiasco🤮🤮

That’s a bit patronising, as you know very little of the positions that held in my career. I held programme manager positions for procuring defence equipments which obviously had complex contracts, then on “retiring” I moved into the business world as a supplier of systems and services at a major aero/marine company and latterly at a consultancy. It was “pig in the middle” in fulfilling our contracts to the customer, plus ensuring our suppliers fulfilled their obligations to us. “ Can of worms” could be one description. 😂

 

[Buckman]

That’s a bit patronising, as you know very little of the positions that held in my career. I held programme manager positions for procuring defence equipments which obviously had complex contracts, then on “retiring”

Many years ago I did the same during our bush war. Mainly components for military radios, but as we had sanctions on us. no return if goods were faulty. However failure rate was very low. Mainly US sourced ICs etc. Believe it or not our radios had a substantial amount of NATO components so we knew that were always good.

 

[Dustydog]

I told this before on here.
Decades ago an Italian Company supplied our client with plastic press fit valves for their gas boilers. The plastic valves when fitted fractured but didn’t completely break at first . After 18 months a high frequency of failures were noted in the field all resulting in explosions but fortunately not life threatening.
A very expensive Product Recall exercise was carried out involving numerous countryside gas engineers in the fitting of new reliable valves. Cost over £500k.
The Italians would only pay the original cost of the plastic, pennies.
It wasn’t worth the Legal cost of suing them.

The Prof has also listed a case he had with a caravan manufacturer.
Certainly not a bed of roses as you may think Clive. As the old saying goes “ There’s no friends in business” .
Remember the PPE outstanding fiasco🤮🤮

That’s a bit patronising, as you know very little of the positions that held in my career. I held programme manager positions for procuring defence equipments which obviously had complex contracts, then on “retiring” I moved into the business world as a supplier of systems and services at a major aero/marine company and latterly at a consultancy. It was “pig in the middle” in fulfilling our contracts to the customer, plus ensuring our suppliers fulfilled their obligations to us. “ Can of worms” could be one description. 😂

Certainly not intentionally patronising but from I have seen over the years the only ones who got rich were the Lawyers.