So I have hitched caravan to new car, Hyundai Santa Fe and nose down doesn't do it justice it is so low the jockey wheel cannot clear the fairing on the drawbar looks to me to be at least 2 inches too low, towball height is 13inches to the top of ball from ground, any suggestions please.
TOW BALL HEIGHT
- Thread starter woodsieboy
- Start date
Woodsieboy, mentioned on a previous post, if its a Witter, it sits too low, and too far from the bumper. The cross bar , four bolts can be loosened , jack the towball as high as you can and then retorque to 90 nm. The Witter cross bar has only2 bolts a side, . They also fitted a higher tensile bolt , which didnt cure the problem on Heavier nose loaded caravans. I canged mine to a Towtrust bar, 2 inches closer to the center of the rear axcle and a higher hitch with the van on the back of the car.
The height of a tow ball from the ground with the car fully loaded but with out the caravan on should be 350mm to 420mm from ground.
hope this helps
hope this helps
click said:
Hello Click
Your information is wrong, The EU requirement for cars is the centre of the LOADED tow ball must settle between 350 to 420mm vertically from the Centre of the ball to the ground.
Logically you need to knw the height of the working ball, as trailer manufacturers need to be able to design their products for a controlled range of working heights.
I should also point out that the regulation does not apply to all classes of vehicles, some specialist vehicles E.g. Some 4x4's are exempt.
ProfJohnL said:
Prof,
The EC Directive isn't the easiest document to read, but looking at several tow ball makers/towing websites they all say the car must be in the loaded condition. Reading your advice above I would assume the caravan should be attached to have the tow ball loaded? Which is different to the advice elsewhere. Of course the EC requirement for the caravan.trailer tow hitch height is different too. But when the two come together the outfit should be suitable to tow safely.
woodsieboy said:
What you haven't told us is the height you measured was when the caravan was hitched or not. The important measurement is the height of the hitch when it is loaded with the caravan in its ready to tow configuration. If the measurement is between 300 and 420mm from the centre of the ball to then it should be fine as that is the range teh caravan manufacturers design for. If its less as you are suggesting, then two things to be considered, Firstly is the caravans nose load too much, and is the tow bar on the tow vehicle set up properly.
Beyond that it could be the tow vehicles suspension is over loaded ( load in the car and the nose load) or teh suspension may be faulty.
Hello Clive.
I have studied the actual EU regulation, and it is actually very clear. The outfit in its loaded configuration must settle its coupled towball within the 350 to 420mm range. except where the vehicle is exempt from the regulation. I do not know if the Santa Fe is classed as exempt of not, its usually commercial vehicles that are exempt.
Logically the height of the tow hitch when its working (i.e. towing) is the important factor, as the caravan manufacturers will have designed their products to cope with the 350 to 420mm working range of ball heights. The unloaded height is irrelevant as its not being used. Obviously when any load is applied to a car its suspension will readjust, and that will affect the height of the tow ball, so yes the car should be load ready for towing as well as having the trailer coupled when the ball height is checked.
I have studied the actual EU regulation, and it is actually very clear. The outfit in its loaded configuration must settle its coupled towball within the 350 to 420mm range. except where the vehicle is exempt from the regulation. I do not know if the Santa Fe is classed as exempt of not, its usually commercial vehicles that are exempt.
Logically the height of the tow hitch when its working (i.e. towing) is the important factor, as the caravan manufacturers will have designed their products to cope with the 350 to 420mm working range of ball heights. The unloaded height is irrelevant as its not being used. Obviously when any load is applied to a car its suspension will readjust, and that will affect the height of the tow ball, so yes the car should be load ready for towing as well as having the trailer coupled when the ball height is checked.
ProfJohnL said:
Thanks Prof, that's raised an interesting query in my mind as both Clubs give the 350-420 mm dimension as for a car loaded but not hitched to a caravan or trailer.
My current car has a quite low towball which leads to some light scraping of the jockey wheel as I come off/on the drive. I also have to get right under to fix the breakaway cable and 13 pins electrics. So as with neighbours I may have to take the caravan onto the road using the mover and hitch up when its all level. The drive goes down as the camber of the road goes up which exacerbates it. Other combinations of caravan and car have done the same, so the combination of tow car and caravans have been within the overall specification. (Disco2/Mondeo Gen 1 and 2 + Abi Daystar, Mondeo + Eldiss Hurricane, Sorento/XC70 + Bailey S5 Pageant, Subaru Forester +Trigano 420DD/Sprite Musketeer)
Hello Clive,
Can you point to the particular documents where teh clubs assert the caravan does not need to be hitched? I will be happy to discuss the matter with teh clubs technical directors.
Can you point to the particular documents where teh clubs assert the caravan does not need to be hitched? I will be happy to discuss the matter with teh clubs technical directors.
Sorry but My caravan manual is were I got the info from and they say that is with the car loaded and the caravan not connected
click said:
Measurement under those conditions would pointless and of no value to any one. I took my information directly from the relevant EU regulation.
Reading the EU regulation it is worth pointing out that different values are given for the height ranges of a "Laden" vehicle as opposed to an unhitched but laden caravan.
I do not dispute the Prof's comments which make good sense but I have a bit of difficulty understanding why the EU reg quotes different height values. I wonder why car and caravan are not the same
car 350 mm -420 mm
caravan 385mm -455mm
I do not dispute the Prof's comments which make good sense but I have a bit of difficulty understanding why the EU reg quotes different height values. I wonder why car and caravan are not the same
car 350 mm -420 mm
caravan 385mm -455mm
Prof,
Here are some links that deal with the topic:
https://www.caravanclub.co.uk/media/1022853/choice-of-towbar-mo.pdf
From above link:
In theory, all towbars should set the ball at the correct height. Both the British Standard BS 150 1103:2007 and the EC Directive 94/20/EC, require the centre of the towball, when the towing vehicle is fully laden to its gross vehicle weight (but without the caravan attached) to be between 350 and 420mm from the ground. This should be compatible with any reasonably modern caravan, given one or two provisos:-
If the car manufacturer chooses to set the tow ball height towards the upper end of the height range, and especially if the vehicle has a relatively high load carrying capacity, it may be that under normal operating load conditions the tow ball is significantly higher than this range. This is permissible according to the letter of the standard or directive requirements, but may result in difficulties achieving a well set-up outfit.
However, the most recent link from the C&MHC is delightfully vague and does not address car/van relationship as affecting towball height.
https://www.caravanclub.co.uk/advice-and-training/technical-advice/choice-of-towbar/
This link from Caravan Chronicles mirrors others which seems to show that the towball height is measured on the laden car, but not with the caravan hitched. But different car makers can define "laden" in different ways, viz:
https://caravanchronicles.com/guides/understanding-all-about-tow-ball-height/
Camping and Caravan Club data sheet 29 gives advice on the tow car, towbar, lowball and electrics, and only refers to the lowball standard height range in relation to the laden car. It does not discuss the caravan being attached.
NCC guide September 2014 addresses the towball height within the car section of the document, whereas the tow hitch height is detailed in the caravan section. The NCC guide is "supported" by both clubs.
So only the 2010 CC (C&MHC) technical sheets specifically state that the towball height is related solely to the car in its laden condition. But looking at the other documents I would err on the view that the towball height is measured with the car unhitched but in its laden condition; whatever that is! Our hobby doesn't make things easy for the beginners, or anyone else for that matter does it?
Here are some links that deal with the topic:
https://www.caravanclub.co.uk/media/1022853/choice-of-towbar-mo.pdf
From above link:
In theory, all towbars should set the ball at the correct height. Both the British Standard BS 150 1103:2007 and the EC Directive 94/20/EC, require the centre of the towball, when the towing vehicle is fully laden to its gross vehicle weight (but without the caravan attached) to be between 350 and 420mm from the ground. This should be compatible with any reasonably modern caravan, given one or two provisos:-
If the car manufacturer chooses to set the tow ball height towards the upper end of the height range, and especially if the vehicle has a relatively high load carrying capacity, it may be that under normal operating load conditions the tow ball is significantly higher than this range. This is permissible according to the letter of the standard or directive requirements, but may result in difficulties achieving a well set-up outfit.
However, the most recent link from the C&MHC is delightfully vague and does not address car/van relationship as affecting towball height.
https://www.caravanclub.co.uk/advice-and-training/technical-advice/choice-of-towbar/
This link from Caravan Chronicles mirrors others which seems to show that the towball height is measured on the laden car, but not with the caravan hitched. But different car makers can define "laden" in different ways, viz:
https://caravanchronicles.com/guides/understanding-all-about-tow-ball-height/
Camping and Caravan Club data sheet 29 gives advice on the tow car, towbar, lowball and electrics, and only refers to the lowball standard height range in relation to the laden car. It does not discuss the caravan being attached.
NCC guide September 2014 addresses the towball height within the car section of the document, whereas the tow hitch height is detailed in the caravan section. The NCC guide is "supported" by both clubs.
So only the 2010 CC (C&MHC) technical sheets specifically state that the towball height is related solely to the car in its laden condition. But looking at the other documents I would err on the view that the towball height is measured with the car unhitched but in its laden condition; whatever that is! Our hobby doesn't make things easy for the beginners, or anyone else for that matter does it?
Thankyou Clive,
As we know web sites can mislead, the Government portal is a classic example where they misquoted parts of the driving licence requirements, so if Governments can get it wrong when they're presenting their own information, its entirely possible that third party sites can do an equally incomplete job.
In all matters like this you need to be able to refer to the formulation or legislative document rather than interpretations of them. In this case the relevant document is the one quoted in the CC document you first quote EC Directive 94/20/EC.
If you search for the document look up Figure 30 (about 75% into the document, the specification for the height of the coupling above the ground is given as 350 to 420, with a a note "Vehicle Load" It does not specify if the hitch is coupled or not.
But it's an intrinsic fact that when a trailer is coupled, the nose load is transferred to the tow vehicle and becomes part the the tow cars "load" So provided the cars gross load does not exceed its specification, then even when a trailer is coupled it must still comply with the 350 to 420 limit.
As we know web sites can mislead, the Government portal is a classic example where they misquoted parts of the driving licence requirements, so if Governments can get it wrong when they're presenting their own information, its entirely possible that third party sites can do an equally incomplete job.
In all matters like this you need to be able to refer to the formulation or legislative document rather than interpretations of them. In this case the relevant document is the one quoted in the CC document you first quote EC Directive 94/20/EC.
If you search for the document look up Figure 30 (about 75% into the document, the specification for the height of the coupling above the ground is given as 350 to 420, with a a note "Vehicle Load" It does not specify if the hitch is coupled or not.
But it's an intrinsic fact that when a trailer is coupled, the nose load is transferred to the tow vehicle and becomes part the the tow cars "load" So provided the cars gross load does not exceed its specification, then even when a trailer is coupled it must still comply with the 350 to 420 limit.
Thanks for all these fantastic EU regs,
BUT, The witter tow bar on the Sante Fe, "Drops " due to an engineering problem, Witter has recognised this but have failed to recall. The fix is to have stronger bolts and higher torque on the cross bar bolts. This works except when you have an Alko tow hitch which gives an added 150 mm from the centernof the rear axle , giving an extra load to the croß tube. Can not say more otherwise The company concerned might slander me.,
BUT, The witter tow bar on the Sante Fe, "Drops " due to an engineering problem, Witter has recognised this but have failed to recall. The fix is to have stronger bolts and higher torque on the cross bar bolts. This works except when you have an Alko tow hitch which gives an added 150 mm from the centernof the rear axle , giving an extra load to the croß tube. Can not say more otherwise The company concerned might slander me.,
Having had a little more time to check out the documents that Clive has brought to our attention, the commonly held and repeated discrepancy concerning the coupling height is down to the fact they are actually describing two different characteristics of the coupling arrangements.
In the standards particular attention needs to be give to the descriptions of the characteristics used specifically the "Ball" relates to the part attached to the tow vehicle, and the "Coupling Head" relates to the part attached to the trailer.
The element we have been discussing is the height of the tow ball when it is used for towing, and that still remains as 350 to 420mm ground to centre of the ball. Some tow vehicles are exempt from this regulation see regulation 2.1.1. However whether the 'Santa Fe' falls into this exemption I do not know.
The other figure that appears in parts of documentation Clive has identified is 430 +/-35mm to the geometric centre of the coupling head. This appears to be at odds with the Ball hitch height, but it is in fact the measurement for a different characteristic. It relates to a constructional requirement for the height of the coupling head on the trailer (not the ball on the tow vehicle) when the trailer is uncoupled and trimmed to give a horizontal load surface.
With trailers coupling heads (430 +/-35mm) on average higher than the range of tow vehicle ball heights (350 to 420mm), this will tend to give most caravans a nose down characteristic when being towed. But within the height ranges it is perfectly possible for some caravans to actually have a nose up attitude when being towed.
Again contrary to popular belief a nose up attitude created by these ranges is not automatically or intrinsically unsafe.
In the standards particular attention needs to be give to the descriptions of the characteristics used specifically the "Ball" relates to the part attached to the tow vehicle, and the "Coupling Head" relates to the part attached to the trailer.
The element we have been discussing is the height of the tow ball when it is used for towing, and that still remains as 350 to 420mm ground to centre of the ball. Some tow vehicles are exempt from this regulation see regulation 2.1.1. However whether the 'Santa Fe' falls into this exemption I do not know.
The other figure that appears in parts of documentation Clive has identified is 430 +/-35mm to the geometric centre of the coupling head. This appears to be at odds with the Ball hitch height, but it is in fact the measurement for a different characteristic. It relates to a constructional requirement for the height of the coupling head on the trailer (not the ball on the tow vehicle) when the trailer is uncoupled and trimmed to give a horizontal load surface.
With trailers coupling heads (430 +/-35mm) on average higher than the range of tow vehicle ball heights (350 to 420mm), this will tend to give most caravans a nose down characteristic when being towed. But within the height ranges it is perfectly possible for some caravans to actually have a nose up attitude when being towed.
Again contrary to popular belief a nose up attitude created by these ranges is not automatically or intrinsically unsafe.
Prof,
Thanks for the steer to Figure 30 of the EC Directive. I must say for what is supposed to be a definitive document it can be lacking in clarity. I have tried to find if anything has been embodied within the UK Construction and Use Regs but no success. Looking at Fig 30 it is ambiguous as one could consider the text "Vehicle load" to relate to the direction of downforce applied by the coupling head in relation to the ground. Alternatively you could also understand it to be related to the trailer noseweight value. A final option could be to read it as "Vehicle Load" meaning the car is loaded to GVW/MAM. However looking at the earlier pages of the Directive the definition of Vehicle includes for the trailer.
So where does this leave me. Well certainly the range of height for the towball should reflect the value when the car is at GVW/MAM, which has to include for the noseweight applied by the caravan coupling as this is part of the car's load. It isn't necessary to measure the towball height with the caravan attached as the car can be loaded up to its GVW/MAM although some may say that not having the 60-100kg noseweight of the van aft of the axle doesn't give a true representation of the effect of the force-lever arm on the towball height.
So i think that measuring the towball centre height is valid with or without the caravan attached providing the car's load at the time of measuring reflects the effect of the noseweight on GVW/MAM. What I find surprising in this discussion is that such erudite bodies as the Clubs and NCC can make what should be a simple definition so puzzling. But that's caravanning for you!
Thanks for the steer to Figure 30 of the EC Directive. I must say for what is supposed to be a definitive document it can be lacking in clarity. I have tried to find if anything has been embodied within the UK Construction and Use Regs but no success. Looking at Fig 30 it is ambiguous as one could consider the text "Vehicle load" to relate to the direction of downforce applied by the coupling head in relation to the ground. Alternatively you could also understand it to be related to the trailer noseweight value. A final option could be to read it as "Vehicle Load" meaning the car is loaded to GVW/MAM. However looking at the earlier pages of the Directive the definition of Vehicle includes for the trailer.
So where does this leave me. Well certainly the range of height for the towball should reflect the value when the car is at GVW/MAM, which has to include for the noseweight applied by the caravan coupling as this is part of the car's load. It isn't necessary to measure the towball height with the caravan attached as the car can be loaded up to its GVW/MAM although some may say that not having the 60-100kg noseweight of the van aft of the axle doesn't give a true representation of the effect of the force-lever arm on the towball height.
So i think that measuring the towball centre height is valid with or without the caravan attached providing the car's load at the time of measuring reflects the effect of the noseweight on GVW/MAM. What I find surprising in this discussion is that such erudite bodies as the Clubs and NCC can make what should be a simple definition so puzzling. But that's caravanning for you!
Hello again Clive,
I do agree it takes a lot of careful research to get to the bottom of these reg's. I wish they were more accessible. But whilst they do appear to be complicated they are actually logical, and necessary. Unfortunately the wording of these directives are very precise, hence the need to differentiate between for example "Ball" and "coupling head"
The ball height should be compliant when the tow vehicle is loaded to its MAM, but in reality how many people would know when their vehicle is loaded to its limit to be able to check? I'd venture not many.
The simplest way to check compliance is to have the caravan coupled and then measure the height, after all that's how its going to be used!
I do agree it takes a lot of careful research to get to the bottom of these reg's. I wish they were more accessible. But whilst they do appear to be complicated they are actually logical, and necessary. Unfortunately the wording of these directives are very precise, hence the need to differentiate between for example "Ball" and "coupling head"
The ball height should be compliant when the tow vehicle is loaded to its MAM, but in reality how many people would know when their vehicle is loaded to its limit to be able to check? I'd venture not many.
The simplest way to check compliance is to have the caravan coupled and then measure the height, after all that's how its going to be used!
Facebook
Twitter