I just got this in a Facebook group and though the antics of the presenter are tiresome, the message is still valid.
When pointed out it is obvious that WDH will add stresses along the caravan chassis, but that a stress fracture could be created under the van body never occurred to me. I had seen photos of drawbar failure previously but the danger of stress fractures under the van body never occurred to me.
The van owners were very lucky to spot this.
Question is what would be the reaction from the insurers, dealers or manufacturers if it happened to you?
I just got this in a Facebook group and though the antics of the presenter are tiresome, the message is still valid.
When pointed out it is obvious that WDH will add stresses along the caravan chassis, but that a stress fracture could be created under the van body never occurred to me. I had seen photos of drawbar failure previously but the danger of stress fractures under the van body never occurred to me.
The van owners were very lucky to spot this.
Question is what would be the reaction from the insurers, dealers or manufacturers if it happened to you?
And again.Telling the truth will no doubt upset a few. Gotta go to work now, but late tonight I may add to this thread. The stresses imposed on both car and van by a WDH are enormous, but few have a clue. Thanks for posting. Cheers
-- Edited by yobarr on Thursday 4th of May 2023 07:30:34 AM
This is the second such picture of this type of A frame failure that has appeared in this forum recently. I can only wonder how many others have happened, and more importantly, has such a failure caused an accident.
Like the first one a couple of weeks ago what I find it interesting is that both cases show a clean break with no distortion.
While no doubt the down force applied by WDH has caused the break, that only happened because the A frame was never constructed with sufficient strength to take in account that caravan owners may use a WDH.
My 2014 Jayco Sterling has reinforcing along the bottom of each side of the A frame. Whether by the factory or previous owner I don't know. As the front of my Ranger only lifts about 20mm (measured!) when coupled up so I have not required a WDH.
If failure of the A frame caused by WDHs is common then the caravan industry will have to provide A frames with sufficient strength to prevent that.
There are many reasons for stress fractures in structures that can be and probably are entirely unrelated to the use of a WDH.
Poor quality steel using Chinesium and there have been quite a few failures in building structures found to be caused by that. Why would van chassis be any different?
Insufficient sizing of components by the manufacturer for the expected loads placed on the structure.
Poor quality welds or welding techniques causing failure of the weld or in the heat zone either side of the weld with changes to the crystalline structure of the base material
Overloading by the user past the structures design load.
With a WDH, lack of understanding of how the hitch works and therefore incorrect fitting or usage of the hitch causing overloading of the drawbar and towbar attachment points.
Using the WDH in situations it should not be used such as off road.
Unfortunately, like broken dual cab Ute chassis's, the full circumstances of such failures are rarely examined, save for some half baked commentary on forums such as this that then rule that that product or vehicle can't be too good because look at that failure, without knowing all the facts.
So to add to my post above after watching the video.
Firstly the lady in question is towing her van with a truck.
It is well known that structural failures of trailer chassis when towing with a truck is quite common unless either the chassis of the trailer is designed for it or the truck is fitted with a cushioned or sprung hitch system. This is due to the very stiff load carrying suspension of the truck.
Secondly, if towing with a truck, why would you need a WDH in the first instance as the truck would barely notice the van weight on the towbar.
Codogan's comments about the incorrect use of a WDH is very valid and I have seen many who have so much tension placed into the bars statically that they are a failure looking for a place to happen.
It is also about time that authorities demanded engineering certificates from trailer chassis manufacturers with regards to the design and construction of their chassis issued by an approved engineer.
When building the little car in my avatar, I had to have a full report on chassis stiffness and design by an approved engineer to be able to register the vehicle. At last count, that wasn't the case with trailers.
There are many reasons for stress fractures in structures that can be and probably are entirely unrelated to the use of a WDH. Poor quality steel using Chinesium and there have been quite a few failures in building structures found to be caused by that. Why would van chassis be any different? Insufficient sizing of components by the manufacturer for the expected loads placed on the structure. Poor quality welds or welding techniques causing failure of the weld or in the heat zone either side of the weld with changes to the crystalline structure of the base material Overloading by the user past the structures design load. With a WDH, lack of understanding of how the hitch works and therefore incorrect fitting or usage of the hitch causing overloading of the drawbar and towbar attachment points. Using the WDH in situations it should not be used such as off road. Unfortunately, like broken dual cab Ute chassis's, the full circumstances of such failures are rarely examined, save for some half baked commentary on forums such as this that then rule that that product or vehicle can't be too good because look at that failure, without knowing all the facts.
x2 Greg.
Yobarr's pic has been used that many times I think it might be his van. No proof the break was caused by a WDH at all, could have been one of those truckies running some vanner off the road.
There are many reasons for stress fractures in structures that can be and probably are entirely unrelated to the use of a WDH. Poor quality steel using Chinesium and there have been quite a few failures in building structures found to be caused by that. Why would van chassis be any different? Insufficient sizing of components by the manufacturer for the expected loads placed on the structure. Poor quality welds or welding techniques causing failure of the weld or in the heat zone either side of the weld with changes to the crystalline structure of the base material Overloading by the user past the structures design load. With a WDH, lack of understanding of how the hitch works and therefore incorrect fitting or usage of the hitch causing overloading of the drawbar and towbar attachment points. Using the WDH in situations it should not be used such as off road. Unfortunately, like broken dual cab Ute chassis's, the full circumstances of such failures are rarely examined, save for some half baked commentary on forums such as this that then rule that that product or vehicle can't be too good because look at that failure, without knowing all the facts.
x2 Greg.
Yobarr's pic has been used that many times I think it might be his van. No proof the break was caused by a WDH at all, could have been one of those truckies running some vanner off the road.
What do you reckon Doug?
Hi Bob, Just wondering why you would be asking Doug about engineering, considering Greg's excellent explanation above?
Anyway, back to the topic being discussed. Many times I have stated that a WDH is used, and sometimes recommended only by those who have ulterior motives, or are trying to make a car do things for which it never was designed.
The person who suggested or insisted that a WDH be used on a TRUCK towing a 21'6" van should be lined up and shot without trial, figuratively speaking.
The TRUCK in question has a rear axle capacity of 4400kg and front axle capacity of 2600kg .
Even a 350kg towball weight would have negligible effect on the truck's rear axle, and there would be zero need to transfer weight to the truck's front axle. Spare me!
This lady could, unfortunately, have big problems as the effects of a heavy truck towing a caravan are well recognised, and the WDH used would only have exacerbated those negative effects. Stupidity in the extreme.
Unfortunately, few understand what a WDH is "designed" to do, and even fewer realise that it is NOT the universal cure-it-all that so many starry-eyed users believe it to be. The number of these contraptions that I've seen on my travels that being used incorrectly is staggering.
Just this week I saw an example of the much overrated LC200 with a WDH wound up so far that the headlights of the car were pointed down towards the ground. There would have been so little weight on the car's rear axle that it was an accident looking for a place to happen. Think "oversteer".
When I bought my 3500kg van, long before I studied the effects of a WDH, I was convinced to part with a pile of cash to purchase a nice WDH system. When I fitted it, as per instructions, it soon became apparent to me that there would be a massive downforce on the 'A' frame around half-way along its length.
Despite my van having a full chassis built from 6" x 2" box section steel, with cross members, I decided that the downforce applied to the 'A' frame by the WDH was too great to be ignored, so I reinforced from under the 'A' frame to under the van, as per picture. Where the arrow points there is a small steel roller designed accomodate flexing.
Although the 79 has a factory rated 2300kg rear axle I was convinced by those with ulterior motives to fit this contraption, and away I went.
What an absolute waste of money that was, as it was soon apparent that at 6800kg GCM ALL my weights were safe and legal and that the car felt better without it.
Not being one to try to recuperare a couple of miserable dollars by selling it I simply cut my losses by removing it, then giving it to someone I don't particularly like. He was ecstatic but I simply gave him a wry smile.
My best wishes are directed to the lady who owns the broken 'A' frame, and virtually written-off, caravan as I fear that the insurance company will quickly realise that the WDH contributed to the damage. Very sad.
Again I will say that WDH is used only to make a car do things for which it never was designed. Cheers
-- Edited by yobarr on Saturday 6th of May 2023 04:57:11 PM
Hi Bob, Just wondering why you would be asking Doug about engineering, considering Greg's excellent explanation above?
Anyway, back to the topic being discussed. Many times I have stated that a WDH is used, and sometimes recommended only by those who have ulterior motives, or are trying to make a car do things for which it never was designed.
The person who suggested or insisted that a WDH be used on a TRUCK towing a 21'6" van should be lined up and shot without trial, figuratively speaking.
The TRUCK in question has a rear axle capacity of 4400kg and front axle capacity of 2600kg .
Even a 350kg towball weight would have negligible effect on the truck's rear axle, and there would be zero need to transfer weight to the truck's front axle. Spare me!
This lady could, unfortunately, have big problems as the effects of a heavy truck towing a caravan are well recognised, and the WDH used would only have exacerbated those negative effects. Stupidity in the extreme.
Unfortunately, few understand what a WDH is "designed" to do, and even fewer realise that it is NOT the universal cure-it-all that so many starry-eyed users believe it to be. The number of these contraptions that I've seen on my travels that being used incorrectly is staggering.
Just this week I saw an example of the much overrated LC200 with a WDH wound up so far that the headlights of the car were pointed down towards the ground. There would have been so little weight on the car's rear axle that it was an accident looking for a place to happen. Think "oversteer".
When I bought my 3500kg van, long before I studied the effects of a WDH, I was convinced to part with a pile of cash to purchase a nice WDH system. When I fitted it, as per instructions, it soon became apparent to me that there would be a massive downforce on the 'A' frame around half-way along its length.
Despite my van having a full chassis built from 6" x 2" box section steel, with cross members, I decided that the downforce applied to the 'A' frame by the WDH was too great to be ignored, so I reinforced from under the 'A' frame to under the van, as per picture. Where the arrow points there is a small steel roller designed accomodate flexing.
Although the 79 has a factory rated 2300kg rear axle I was convinced by those with ulterior motives to fit this contraption, and away I went.
What an absolute waste of money that was, as it was soon apparent that at 6800kg GCM ALL my weights were safe and legal and that the car felt better without it.
Not being one to try to recuperare a couple of miserable dollars by selling it I simply cut my losses by removing it, then giving it to someone I don't particularly like. He was ecstatic but I simply gave him a wry smile.
My best wishes are directed to the lady who owns the broken 'A' frame, and virtually written-off, caravan as I fear that the insurance company will quickly realise that the WDH contributed to the damage. Very sad.
Again I will say that WDH is used only to make a car do things for which it never was designed. Cheers
- Edited by yobarr on Saturday 6th of May 2023 04:57:11 PM
I would love to see you engineering qualificatios yobarr.
but as usual you spew anti WDH rubbish but I'm sure that those of us who use our WDH's according to the manufactures instructions and according to our vehicle manufacture requirements travel safely.
I would love to see you engineering qualificatios yobarr.
but as usual you spew anti WDH rubbish but I'm sure that those of us who use our WDH's according to the manufactures instructions and according to our vehicle manufacture requirements travel safely.
Graham, I am exceedingly happy that your setup pleases you, but surely you can understand that if your car is designed and marketed as being able to tow 3000kg (or whatever your rating is) then surely it should be able to do this without the use of towing aids?
The fact that a manufacturer suggests, recommends or whatever the term you wish to use is, the use of such a device is surely an admission that they realise that the rear axle of the car is not up to the allocated towing task, when towing a PIG trailer, IMO.
You evidently need a bigger car or a smaller van, because if safety is of any concern, always the weight on the wheels of the car should be at least 10% greater than the weight on the wheels of the van. Simple physics.
These are facts that are not eagerly accepted by the many adoring fans of WDH units, but they are simply that, IMO. Facts.Cheers
-- Edited by yobarr on Saturday 6th of May 2023 08:15:32 PM
I seem to be missing something here, where is it mandated that a WDH must be used? My tow vehicle was bought new with factory tow kit fitted, the manual has no reference to WDH.
Caravan manufacturer does not mention WDH, is it only needed if I want to try and exceed the limits I have been given??
I seem to be missing something here, where is it mandated that a WDH must be used? My tow vehicle was bought new with factory tow kit fitted, the manual has no reference to WDH. Caravan manufacturer does not mention WDH, is it only needed if I want to try and exceed the limits I have been given??
Tow kit and WDH are two completely different things. If you care to supply your car model details and the details of your van I can advise. Need ATM of van, and axle group rating (AGR) if possible. Some vans have GTM supplied on compliance plate. This would be a help too. Tare means nothing. Cheers
Thanks mate but I think you are missing my point. I ordered a vehicle with factory tow bar, elec brakes etc set up to tow 3 T, bought a van that runs less than 3 T, where is the requirement to run a WDH laid down? People that have one seem to swear by them, I do not see people saying that using one improves things, but carrying extra weight and adding extra stresses has to be a negative.
Thanks mate but I think you are missing my point. I ordered a vehicle with factory tow bar, elec brakes etc set up to tow 3 T, bought a van that runs less than 3 T, where is the requirement to run a WDH laid down? People that have one seem to swear by them, I do not see people saying that using one improves things, but carrying extra weight and adding extra stresses has to be a negative.
Hi Barney, my model Ford Ranger its mandatory to use a WDH when towing over 1800kg, its pretty simple when you weigh the front axle after connecting the caravan with a 8-10% ball weight too much weight come off the front axle.
If the weight is not returned to front axle then in certain conditions you could have understeer and the front braking could be effected.
When the WDH is setup and engaged correctly weight is transfered back to the front axle group, thus returning steering and braking are positive.
If the WDH wasnt used I would be an accident looking for somewhere to happen.
The all knowing Mr yobarr because it dosnt fit his narritive he pooha's their use, even Toyota in their towing guide reccommend the use of a WDH for the 200 series.
Just for the record I have been using WDH'd since 1980.
PS Caravan Manufactures dont decide if you need a WDH, its the vehicle manufactures some do and other dont.
Thanks mate but I think you are missing my point. I ordered a vehicle with factory tow bar, elec brakes etc set up to tow 3 T, bought a van that runs less than 3 T, where is the requirement to run a WDH laid down? People that have one seem to swear by them, I do not see people saying that using one improves things, but carrying extra weight and adding extra stresses has to be a negative.
You've got it! More this evening if I get back in time, but I will iterate that a WDH is ysed only to make a car do things for which it was not designed. Think twin-cab utes loaded to the hilt with load behind back axle. Cheers
People seem to think that because some manufacturers mandate or recommend their use then they should be used on all vehicles.
Unfortunately the vast majority of users have no idea what a WDH does or how it works.
Rarely do I see a WDH set up correctly, but regularly owners tell me that their neighbours brother's mate said a WDH MUST be used, so like sheep they rush out and buy one.
In some circumstances they can be useful, but rarely. Cheers
People seem to think that because some manufacturers mandate or recommend their use then they should be used on all vehicles.
Unfortunately the vast majority of users have no idea what a WDH does or how it works.
Rarely do I see a WDH set up correctly, but regularly owners tell me that their neighbours brother's mate said a WDH MUST be used, so like sheep they rush out and buy one.
In some circumstances they can be useful, but rarely. Cheers
How do you set one up correctly Chris?........or do you ask the Chief?
How do you set one up correctly Chris?........or do you ask the Chief?
The first step in setting up for a caravan, is to establish the height of the towball.
1st off with the caravan on level ground and the with the caravan level, you measure from the ground to the top of the coupling IE 16", therefore you will need to adjust hitch to have the top of the ball to ground 16".
Deciding wether you choose to use a WDH or depends on a number of factors;-
1. What does your vehicle's towing guide or owners handbook advise (In my case Ford for my Model the use of a WDH is required if the trailer exceeds 1800kg)
2. If when you connect the tow vehicle and caravan if the combination has the front vehicle and the rear of the caravan are higher than the rear of the vehicle and front of the caravan. Then you may have to redistribute the load within the caravan to try and get your caravan level.
3. If you cannot get the caravan back to almost level(slightly lower at the front of the van is ok).Then you may need a WDH, consulate with your vehicles service manager for the correct equipment.
4. The fitting of air bags or helper springs are not the solution, talking to stores like ARB etc is a waste of time they are in the business of selling accessories that you may not need.
5. If you choose to use a WDH then follow the instructions supplied for setup and use.
People seem to think that because some manufacturers mandate or recommend their use then they should be used on all vehicles.
Unfortunately the vast majority of users have no idea what a WDH does or how it works.
Rarely do I see a WDH set up correctly, but regularly owners tell me that their neighbours brother's mate said a WDH MUST be used, so like sheep they rush out and buy one.
In some circumstances they can be useful, but rarely. Cheers
How do you set one up correctly Chris?........or do you ask the Chief?
Bob, if I felt that I needed help to set one up correctly you can rest assured that I would seek advice from someone who first of all can convince me that he knows what he is talking about.
There is a no-doubt well-intentioned post that gives advice to "redistribute the load with in the caravan to try and get your caravan level". You would have to be joking, as having the van level is not overly important unless the van has non-load sharing suspension.
The big panic about getting the car and van level is what WDHs were about when Pa Nature played caravans with the HQ and Viscount!
Truly I am amazed that someone would suggest that the load in the van should be moved around in an effort to get the van level.
Has "Yaw" been considered? What about the generally accepted 10% towball weight? As much weight as possible should be directly over the axle group. All water tanks should be plumbed separately with the ability to isolate each tank to help with weight distribution.
There are some no doubt firm believers in using WDHs but the sad truth of the matter is that the vast majority of people using them have absolutely NO idea what the apparatus is supposed to do, and how to make it do that.
When I first joined the forum I posted that a WDH increases the weight of a caravan by imposed more weight on the van's axle group. The flak came from all directions, some of it quite insulting, but I stuck to my guns, posting facts and explaining the physics, and now it appears that many members understand that a WDH increases van weight as it does NOT change towball weight, but puts extra weight on the axle group. In many cases this increase in weight causes the ATM to be exceeded. Overloaded, unsafe and uninsured is the result. Cheers
-- Edited by yobarr on Sunday 7th of May 2023 10:09:52 PM
-- Edited by yobarr on Sunday 7th of May 2023 10:13:33 PM
When I first joined the forum I posted that a WDH increases the weight of a caravan by imposed more weight on the van's axle group. The flak came from all directions, some of it quite insulting, but I stuck to my guns, posting facts and explaining the physics, and now it appears that many members understand that a WDH increases van weight as it does NOT change towball weight, but puts extra weight on the axle group. In many cases this increase in weight causes the ATM to be exceeded. Overloaded, unsafe and uninsured is the result.
Aggregate Trailer Mass (ATM) is the total mass of the trailer when carrying the maximum load recommended by the manufacturer. The ATM is generally measured with the caravan unhitched from your towing vehicle and resting on its jockey wheel.
When I first joined the forum I posted that a WDH increases the weight of a caravan by imposed more weight on the van's axle group. The flak came from all directions, some of it quite insulting, but I stuck to my guns, posting facts and explaining the physics, and now it appears that many members understand that a WDH increases van weight as it does NOT change towball weight, but puts extra weight on the axle group. In many cases this increase in weight causes the ATM to be exceeded. Overloaded, unsafe and uninsured is the result.
Aggregate Trailer Mass (ATM) is the total mass of the trailer when carrying the maximum load recommended by the manufacturer. The ATM is generally measured with the caravan unhitched from your towing vehicle and resting on its jockey wheel.
And your point is? Surely you don't think that the ATM changes or disappears when the trailer is connected to a car? Back to school for you as the weight that was carried by the jockey wheel now is carried by the towbar of tge car.ATM is still same. Cheers
-- Edited by yobarr on Sunday 7th of May 2023 11:04:02 PM
Yobarr, Bill is right. First, the ATM is a rating and never changes. I think you meant Actual Weight.
But how do you measure that when a WDH is connected? What matters, and is measurable is that the weight on the wheels changes, and this may possibly put the van over the GTM.
Whatever the case it is a small amount added, typically about 10-20kg. It's something to be aware of, but to say "In many cases .... etc" would be false. Some cases, yes.
As for the comments on Gundog's list of steps to determine if a WDH is needed, I agree that with load sharing suspension (or single axle), getting the van level is not as important as for non load sharing suspension. Redistributing weight within the van can have benefits. Towards the centre and axles would be positive, but never towards either end, particularly the rear.
If the tug sinks down a lot at the tail when the van is connected, that is a symptom of excessive weight on the towball. Rather than focusing on getting it level, it's the cause that should be addressed and that can't be done with suspension work. That would be a bandaid solution masking the real problem of increased weight on the tug rear wheels and reduced weight on the front wheels.
-- Edited by Are We Lost on Sunday 7th of May 2023 11:34:20 PM
The first step in setting up for a caravan, is to establish the height of the towball.
1st off with the caravan on level ground and the with the caravan level, you measure from the ground to the top of the coupling IE 16", therefore you will need to adjust hitch to have the top of the ball to ground 16". Nothing else matters until you get your towball at the right height.
Deciding wether you choose to use a WDH or depends on a number of factors;-
1. What does your vehicle's towing guide or owners handbook advise (In my case Ford for my Model the use of a WDH is required if the trailer exceeds 1800kg)
2. If when you connect the tow vehicle and caravan if the combination has the front vehicle and the rear of the caravan are higher than the rear of the vehicle and front of the caravan. Then you may have to redistribute the load within the caravan to try and get your caravan level.
3. If you cannot get the caravan back to almost level(slightly lower at the front of the van is ok).Then you may need a WDH, consulate with your vehicles service manager for the correct equipment.
4. The fitting of air bags or helper springs are not the solution, talking to stores like ARB etc is a waste of time they are in the business of selling accessories that you may not need.
5. If you choose to use a WDH then follow the instructions supplied for setup and use.
These are a basic instructions to enable you to travel to a weighbridge to establish the weights applicable to your combination.
If you are like me and are required to use a WDH, then its installation and setup is according to the manufactures instructions generally using the measurement method. Then at the weighbridge you can establish the true GVM, GCM, TBW, GTM and ATM
with that information you can make adjustments to to ensure everything is compliant.
Hi Barney, my model Ford Ranger its mandatory to use a WDH when towing over 1800kg, its pretty simple when you weigh the front axle after connecting the caravan with a 8-10% ball weight too much weight come off the front axle.
I had to wait for a couple of days to retrieve the manual for my Ranger to check.
However, there is no reference whatsoever to using a WDH in it, regardless of the weight towed. Recommended towing weights for 2.2 and 3.2 litre engines, as well as for two or four wheel drive vehicles are given. My Ranger is a 2014 model, perhaps other years may be different.
But it does have these towing gems:
1. Do not exceed 100 km/h even if a country allows higher speeds under certain conditions. And;
2. Use a low gear when descending a steep downhill gradient.
(Sorry for the last two getting away from the WDH topic.)
Murray
Edit: added word towing before gems
-- Edited by Long Weekend on Monday 8th of May 2023 12:44:46 PM
Hi Barney, my model Ford Ranger its mandatory to use a WDH when towing over 1800kg, its pretty simple when you weigh the front axle after connecting the caravan with a 8-10% ball weight too much weight come off the front axle.
I had to wait for a couple of days to retrieve the manual for my Ranger to check.
However, there is no reference whatsoever to using a WDH in it, regardless of the weight towed. Recommended towing weights for 2.2 and 3.2 litre engines, as well as for two or four wheel drive vehicles are given. My Ranger is a 2014 model, perhaps other years may be different.
But it does have these towing gems:
1. Do not exceed 100 km/h even if a country allows higher speeds under certain conditions. And;
2. Use a low gear when descending a steep downhill gradient.
(Sorry for the last two getting away from the WDH topic.)
Murray
Edit: added word towing before gems
-- Edited by Long Weekend on Monday 8th of May 2023 12:44:46 PM
Yes my Ranger is the 2010 3.0 tdi PJ & PK Series, which have the WDH requirement, another variation that can catch PJ&PK owners out is the difference in towing capacity the Automatic is limited 2500kg and Manual is 3000kg. If you have Ford HD towbar, the maximum towball weight is 250kg, this can be overcome by buying a HR towbar for the manual which gives you 3000/300kg.
I have an acquaintance who has a BT50 2010 auto, he was coming out of Mackay heading north just before Kuttabul had the transmission smoking he was over his 2500kg limit and towing in drive, luckily he didn't cook the auto
My Ranger is a 3.2 six speed automatic. I just checked the towbar - it is a factory Ford rated for 350kg (although it is painted black and hard to read I am sure I read it right) tow ball weight.
But the plate carries the warning, basically stating that the weights stated for that particular towbar may not apply for different model Rangers.
Back to the manual. The ratings quoted for both 2x4, 4x4, auto and manual for the 2014 Ranger are the same for each, being 750kg unbraked; 3500kg braked and max gross train weight* of 6000kg.
The rated tow ball weight is shown separate to the table, being the traditional 10% but not to exceed 350kg.
Seems like in the intervening four years between models Ford changed the requirement for a WDH. So we are both right!
Murray
* Train weight? That is a term I haven't seen before. Something for Yobarr to comment on.
And to save Yobarr from commenting, I wouldn't dare try and tow a van at 3,500-kilograms, despite what the manual says!
Yobarr, Bill is right. First, the ATM is a rating and never changes. I think you meant Actual Weight.
Bill is not "right" as this particular piece has been posted in GN several times. No news here.
But how do you measure that when a WDH is connected? What matters, and is measurable is that the weight on the wheels changes, and this may possibly put the van over the GTM.
It is easy to measure the Actual Weight of the trailer when a WDH is fitted. Simply add the weight on van wheels (GTM) to the weight that was on the jockey wheel before the van was connected to the car. A WDH DOES NOT change towball weight, so easy to get Actual Weight.
Depending on car's wheelbase, towball overhang and forward length of van, among other variables, around 30% of weight removed from car's rear axle is transferred to the van's axle group, so your 10-20kg would be incorrect. Been a long day on the Roadtrain so I can't be bothered getting into my files to retrieve exact figures when I played around with a WDH on the 79.
Whatever the case it is a small amount added, typically about 10-20kg. It's something to be aware of, but to say "In many cases .... etc" would be false. Some cases, yes.
As for the comments on Gundog's list of steps to determine if a WDH is needed, I agree that with load sharing suspension (or single axle), getting the van level is not as important as for non load sharing suspension. Redistributing weight within the van can have benefits. Towards the centre and axles would be positive, but never towards either end, particularly the rear. Graham's fixation with having a level van can safely be ignored unless the van has non-load sharing suspension, as can his system of determining if a WDH is needed.
The situation is much more complicated than that, with wheelbase and towball overhang among the many variables. Heavy springs at the rear of a car will cause less change in ride height than lighter springs on the same car, although weight transfer to the rear axle would be the same, almost.
If the tug sinks down a lot at the tail when the van is connected, that is a symptom of excessive weight on the towball. Rather than focusing on getting it level, it's the cause that should be addressed and that can't be done with suspension work. That would be a bandaid solution masking the real problem of increased weight on the tug rear wheels and reduced weight on the front wheels.
The furphy about less weight on front wheels is amusing, as even a 350kg towball weight removes typically 160kg from the car's front axle. If that 160kg change in weight is of concern I suggest that there are bigger issues. Just fit a bullbar. (I jest!) Cheers
-- Edited by yobarr on Tuesday 9th of May 2023 08:34:30 AM
My Ranger is a 3.2 six speed automatic. I just checked the towbar - it is a factory Ford rated for 350kg (although it is painted black and hard to read I am sure I read it right) tow ball weight.
But the plate carries the warning, basically stating that the weights stated for that particular towbar may not apply for different model Rangers.
Back to the manual. The ratings quoted for both 2x4, 4x4, auto and manual for the 2014 Ranger are the same for each, being 750kg unbraked; 3500kg braked and max gross train weight train weight* of 6000kg.
The rated tow ball weight is shown separate to the table, being the traditional 10% but not to exceed 350kg.
Seems like in the intervening four years between models Ford changed the requirement for a WDH. So we are both right!
Murray
*Train weight ? That is a term I haven't seen before. Something for Yobarr to comment on.
Just another stupid terminology for GCM, or total weight of car and van. Gross Combination Mass.
And to save Yobarr from commenting, I wouldn't dare try and tow a van at 3,500-kilograms, despite what the manual says! WELL DONE!
-- Edited by yobarr on Tuesday 9th of May 2023 09:21:32 AM
It is easy to measure the Actual Weight of the trailer when a WDH is fitted. Simply add the weight on van wheels (GTM) to the weight that was on the jockey wheel before the van was connected to the car. A WDH DOES NOT change towball weight, so easy to get Actual Weight.
Yobarr Your total lack of knowledge of physics is again on display. The weight of a caravan is dependent on two factors alone. Its Mass and the acceleration due to gravity neither or which are altered by the use or otherwise of a WDH. Therefore a caravans laden weight (not ATM which a rating) cannot and does not change when a WDH is tensioned
If the weight on the caravans wheels increases then the towball download must be decreased. If you think this is not so then tell me how the mass of the caravan can change or the force of gravity can change when a WDH is tensioned