i would like to put forward the suggestion that all vehicles should have a legally enforcable max tow based on their max nose wt capability.time and again i have people on camp sites tell me how their mondeo or vectra or laguna etc tows their 1500kg van "like its not there",and im sure to take their word for it,but a 1500kg van will present a noseweight of around 100kg,around 20-30kg more than these cars are designed for.surely anyone in this position must be breaking the law and invalidating their insurance and warranty if they have one.the point im making is that we seem to be being misled by kerbweights rather than actual capability.for example the audi a6 tdi listed in pc mag has a kerbweight of 1865,giving an 85% match of 1585.but from the noseweight we can deduce the actual tow figure of 1214kg.should this be made clear in every case?
noseweight v max tow
- Thread starter mcghee
- Start date
Hello Craig,
The nose load presented by a trailer is not a strict proportion of the trailers mass. It is possible to adjust the nose load quite a lot by careful re-loading of the trailer without affecting its overall mass. Thus you cannot extrapolate a trailers mass simply by multiplying the nose load by a fixed factor.
Whilst it is widely recommended that a caravan has a nose load of about 7% of the overall mass. That figure is impractical fro some trailers. The law actually requires a minimum nose load of 25Kg, and the vehicle manufacture will specify the max permitted nose load. Those two limits would be used in any prosecution.
All modern cars do have a max permissible towed mass. This is not directly related to the vertical nose load, as you have observed.
The MTPLM is a legally enforceable figure and if you exceed it you are in breach of the road traffic regulations and your insurance.
As with the vertical nose load, the 85% is only a guide, but you must ensure the towed trailer does not exceed its own permitted maximum mass, or that set by the vehicle manufactures again which ever is lower, and off course you must ensure the gross train mass is maintained below the vehicle manufactures limit.
Mass and weight limits do follow a logical but complicated path. This is the result of having to cope with a wide range of trailers, not simply caravans.
The nose load presented by a trailer is not a strict proportion of the trailers mass. It is possible to adjust the nose load quite a lot by careful re-loading of the trailer without affecting its overall mass. Thus you cannot extrapolate a trailers mass simply by multiplying the nose load by a fixed factor.
Whilst it is widely recommended that a caravan has a nose load of about 7% of the overall mass. That figure is impractical fro some trailers. The law actually requires a minimum nose load of 25Kg, and the vehicle manufacture will specify the max permitted nose load. Those two limits would be used in any prosecution.
All modern cars do have a max permissible towed mass. This is not directly related to the vertical nose load, as you have observed.
The MTPLM is a legally enforceable figure and if you exceed it you are in breach of the road traffic regulations and your insurance.
As with the vertical nose load, the 85% is only a guide, but you must ensure the towed trailer does not exceed its own permitted maximum mass, or that set by the vehicle manufactures again which ever is lower, and off course you must ensure the gross train mass is maintained below the vehicle manufactures limit.
Mass and weight limits do follow a logical but complicated path. This is the result of having to cope with a wide range of trailers, not simply caravans.
I see absolutely no connection between noseweight and towload and consequently no justifiable reason to limit towload on the basis of noseweight.
You seem to referring to the 7% formula that is recommended in some quarters. However, this recommendation does not appear to have ever been established on the basis of any scientific tests and I assume that it was just determined because it 'sounded about right', in the days before car manufacturers laid down relevant specifications.
Fact is that stability improves with noseweight and one should therefore go as high as the car or towbar will allow, regardless of the weight of the trailer.
Max. noseweight is determined by structural criteria only whereas max. towload depends on a lot more (braking and clutch performance, engine and transmission cooling, vehicle handling capability, etc.)
You seem to referring to the 7% formula that is recommended in some quarters. However, this recommendation does not appear to have ever been established on the basis of any scientific tests and I assume that it was just determined because it 'sounded about right', in the days before car manufacturers laid down relevant specifications.
Fact is that stability improves with noseweight and one should therefore go as high as the car or towbar will allow, regardless of the weight of the trailer.
Max. noseweight is determined by structural criteria only whereas max. towload depends on a lot more (braking and clutch performance, engine and transmission cooling, vehicle handling capability, etc.)
your points are all gladly taken on board guys but no matter how you try to adjust the noseweight on a 1500kg van itl probably not be any less than 85-90kg.the point im making is that if a car manufacturer states a max noseload of 75kg,and your applies 85-90kg then you are beyond th safe limit of that vehicle.
I hesitate to tread where more experienced caravanners have ventured, but whatever you guys say, one fact is surely incontravertible - the maximum hitch limit of a towcar should not be exceeded
And from what you say Craig there's an awful lot of caravanners out there who are towing with excessive noseweights, all exacerbated by manufacturers designing vans heavily loaded up at the front, regardless of overall weight!
MIROs and MTPLMs are industry standards for caravan specifications - I suggest a better solution would be another one, NWEFL - Noseweight With Empty Front Locker. Then we'd all know whether the vans in question are compatible with our tow cars in this important respect.
And from what you say Craig there's an awful lot of caravanners out there who are towing with excessive noseweights, all exacerbated by manufacturers designing vans heavily loaded up at the front, regardless of overall weight!
MIROs and MTPLMs are industry standards for caravan specifications - I suggest a better solution would be another one, NWEFL - Noseweight With Empty Front Locker. Then we'd all know whether the vans in question are compatible with our tow cars in this important respect.
thats exactly what im coming around to colin.the noseweight is the load which acts directly on the car and i believe this should be one of the first considerations when buying any van.at the end of the day if your noseweights ok,your vans probably light enough for your car but the reverse isnt necessarily true.
There is absolutely no reason why a 1500kg or even a 1600kg caravan should not have a 75kg max. noseload. If the 'van as delivered and unladen already has such a high noseload that it becomes difficult to adjust down to 75kg without resorting to drastic measures such as placing heavy items at the very rear, then the design is unfit for what it was intended and it is my view that the caravan manufacturer should be held responsible for a gross design error.
Max. noseweight is an absolute figure, Colin, and it is determined by what the towbar and car underbody will structurally take without danger of material failure. It must never be exceeded, whether there is anything in the front locker or not.
Judging by several responses recently in this forum, the problem appears to be difficulty in staying within the maximum limit rather than achieving the legal minimum of 25kg.
Don't forget that it's not only the noseload spec of the car and towbar which limits how high you can go but also the maximum permissible figure for the caravan itself.
I have checked the specs of a few caravans and although I couldn't find any in the 1500-1600kg range with a max. noseload of 75kg (100kg seems to be the norm here), quite a lot of the really big caravans between 1800kg and 2000kg also have a 100kg noseload limit, regardless of any higher figure for the car.
I have checked the specs of a few caravans and although I couldn't find any in the 1500-1600kg range with a max. noseload of 75kg (100kg seems to be the norm here), quite a lot of the really big caravans between 1800kg and 2000kg also have a 100kg noseload limit, regardless of any higher figure for the car.
Lutz
The bigger van noseweight is not down to the manufacturer. it is often a restriction of the tow head used. the Alko on my Ace restricts it to 100kg.
Steve
The bigger van noseweight is not down to the manufacturer. it is often a restriction of the tow head used. the Alko on my Ace restricts it to 100kg.
Steve
As some of you will know, we have an Eriba Triton (MPTLM of 1200kg) and the nose-weight of the fully laden van is usually in the region of 35kg.
When totally unladen this particular model has a nose-weight of around 5kg - and needs two gas bottles in the locker to comply with the legal minimum nose-weight.
Totally stable, never affected by side-winds or trucks - the aerodynamic shape rather than a flat sided box certainly helps here.
It's been our experience that nose-weight and stability are inbuilt by the caravan designer.
A heavier van need not have an excessive nose-weight, but a very high nose-weight may well indicate poor design.
Robert
When totally unladen this particular model has a nose-weight of around 5kg - and needs two gas bottles in the locker to comply with the legal minimum nose-weight.
Totally stable, never affected by side-winds or trucks - the aerodynamic shape rather than a flat sided box certainly helps here.
It's been our experience that nose-weight and stability are inbuilt by the caravan designer.
A heavier van need not have an excessive nose-weight, but a very high nose-weight may well indicate poor design.
Robert
If the manufacturer wants to raise the noseload to over 100kg, AlKo will provide an appropriate coupling head. The AlKo 3004, for example, is designed for up to 150kg. So, in the end, it is up to the caravan manufacturer.
You may have a van empty with a heavy noseweight but it could have the wardrobes/kitchen at the back or like my own Ace the leisure battery which reduces the noseweight considerably
Quite so Lutz but I was trying to make the point that the heavy noseweight although within the limits ex- works could be reduced not increased as had been inferred (it often is increased but not always).
This forum is good in that all aspects are explored and any ambiguity is soon sorted out .
Regards
Generally speaking, the way that people adjust a van's noseweight is to add or remove items from the front locker.
If people knew the noseweight of the unladen caravan with the locker empty, they could better judge whether they could make the necessary adjustment to make the noseweight compatible with their car.
For example, if a mean noseweight was 90-100 kgs, then a prospective purchaser would know that it wd be impossible to achieve a car's limit of 75kg. In which case that van would be deemed unsuitable for him, just as if it had been too heavy in terms of the MIRO.
My point is that everyone is quick to establish the MIRO (it's stamped on the van, by law, I believe) - but frequently overlook the noseweight figure until it's too late.
I don't have a problem with caravans being front heavy - just so long as the mean noseweight figure of a particular model is placed right up there with the MIRO/MTPLM figures so that prospective buyers can rule them out, if necessary, straight away.
If people knew the noseweight of the unladen caravan with the locker empty, they could better judge whether they could make the necessary adjustment to make the noseweight compatible with their car.
For example, if a mean noseweight was 90-100 kgs, then a prospective purchaser would know that it wd be impossible to achieve a car's limit of 75kg. In which case that van would be deemed unsuitable for him, just as if it had been too heavy in terms of the MIRO.
My point is that everyone is quick to establish the MIRO (it's stamped on the van, by law, I believe) - but frequently overlook the noseweight figure until it's too late.
I don't have a problem with caravans being front heavy - just so long as the mean noseweight figure of a particular model is placed right up there with the MIRO/MTPLM figures so that prospective buyers can rule them out, if necessary, straight away.
Sorry to keep going on about this subject but as you've probably guessed, weights and dimensions are a favourite topic of mine.
I therefore repeat my statement that any small to medium sized caravan which has a noseweight of 90 or 100kg in the unladen condition is simply badly designed. The caravan manufacturers must be fully aware that the average car and towbar has a 75kg limit and I feel it's their duty to design products with this in mind. The market would be sadly depleted if everyone were forced to buy a car with a 100kg noseweight limit. The caravan manufacturers would be cutting their own throats. Conversely, it would be unrealistic to expect the car manufacturers to change their designs so that 100kg is always possible. This would often require additional measures to reinforce the underbody structure which would make the product unnecessarily more expensive, especially for the majority of motorists who never use the car for towing purposes.
Because of its legal significance, it is also the dealer's responsibility to make potential purchasers aware of the actual noseweight.
The caravan industry is simply being let off the hook too easily.
I therefore repeat my statement that any small to medium sized caravan which has a noseweight of 90 or 100kg in the unladen condition is simply badly designed. The caravan manufacturers must be fully aware that the average car and towbar has a 75kg limit and I feel it's their duty to design products with this in mind. The market would be sadly depleted if everyone were forced to buy a car with a 100kg noseweight limit. The caravan manufacturers would be cutting their own throats. Conversely, it would be unrealistic to expect the car manufacturers to change their designs so that 100kg is always possible. This would often require additional measures to reinforce the underbody structure which would make the product unnecessarily more expensive, especially for the majority of motorists who never use the car for towing purposes.
Because of its legal significance, it is also the dealer's responsibility to make potential purchasers aware of the actual noseweight.
The caravan industry is simply being let off the hook too easily.
Hello again Craig,
As Lutz has said, and as I indicated in my first response, you cannot mathematically link the nose load with MTPLM of the caravan by a simple constant factor.
By re-arranging the loading of a trailer you can drastically affect the imposed nose load on the hitch, and that is the method you should apply to bring the nose load within the permitted limits for the vehicles in question. By doing so you are not affecting the MTPLM.
I would also agree with Lutz that caravan manufacturers are guilty of complicating the issue by designs that create greater nose loads than the what seems to be car manufactures norm of about 75Kg. They should make this a consideration of the design, and perhapse aim at a load of 60Kg for a caravan in MIRO thus allowing some scope for the nick nacks that usually end up in the front locker.
As Lutz has said, and as I indicated in my first response, you cannot mathematically link the nose load with MTPLM of the caravan by a simple constant factor.
By re-arranging the loading of a trailer you can drastically affect the imposed nose load on the hitch, and that is the method you should apply to bring the nose load within the permitted limits for the vehicles in question. By doing so you are not affecting the MTPLM.
I would also agree with Lutz that caravan manufacturers are guilty of complicating the issue by designs that create greater nose loads than the what seems to be car manufactures norm of about 75Kg. They should make this a consideration of the design, and perhapse aim at a load of 60Kg for a caravan in MIRO thus allowing some scope for the nick nacks that usually end up in the front locker.
Towing a 1500kg caravan, whose noseweight is adjusted to 75kg, is unlikely to be comfortable for any CAR.
Few cars, excluding SUV/4x4's, exceed 1500kg kerbweight let alone the 1765kg needed to meet the 85% guideline.
75kg noseweight isn't unduly light for a 1500kg van, it's 5%, and shouldn't trouble a suitably matched tow vehicle BUT I'd respectfully suggest that those towing with cars, as opposed to SUV/4x4's, should choose lighter caravans.
Caravan manufacturers will, by and large, produce what the market wants. Currently that's larger, well equipped, heavier caravans that can be towed by 4x4's.
Most full size 4x4's have noseweight limits significantly higher than the 75kg commonly found on cars.
As caravan weights continue to rise faster than car weights, it's going to be even more difficult to find a new caravan which can be towed comfortably by a car.
I don't personally like this situation, a I tow with medium saloon, but it's a fact of life.
Few cars, excluding SUV/4x4's, exceed 1500kg kerbweight let alone the 1765kg needed to meet the 85% guideline.
75kg noseweight isn't unduly light for a 1500kg van, it's 5%, and shouldn't trouble a suitably matched tow vehicle BUT I'd respectfully suggest that those towing with cars, as opposed to SUV/4x4's, should choose lighter caravans.
Caravan manufacturers will, by and large, produce what the market wants. Currently that's larger, well equipped, heavier caravans that can be towed by 4x4's.
Most full size 4x4's have noseweight limits significantly higher than the 75kg commonly found on cars.
As caravan weights continue to rise faster than car weights, it's going to be even more difficult to find a new caravan which can be towed comfortably by a car.
I don't personally like this situation, a I tow with medium saloon, but it's a fact of life.
hi everyone.to go back to my initial suggestion.its quite right that you can adjust the noseweight of your van with clever loading but from the number of outfits ive seen with the hitch almost scraping the tarmac id say it doesnt work that well in every case.why doesnt the manufacturers weight plate also show the actual noseweight at miro and the theoretical noseweight at mtplm?none of us would tow a van which was 25% heavier than our car,so why attempt a noseweight that may be 25% too high?
As relatively few people can afford the luxury of having a dedicated towcar and most of our motoring is still done without towing a caravan, the choice of car is usually determined more by one's financial means and one's expectations from the vehicle when driving solo. Towing requirements often take second priority. Most people will therefore continue to use cars instead of 4x4's as a towcar even though caravans are getting heavier and weight ratios will continue to increase.
The industry should face up to the this fact and provide the necessary features to allow safe towing under increasingly unfavourable weight ratio conditions. Electronic stabilisers and tyre pressure monitors should at least be available as factory-fitted options for caravans, just as ESP+ is becoming standard on many new cars. All these devices are readily available but the manufacturers seem to be hesitant to offer them. The car industry is making improvements but caravan chassis design hasn't advanced much since the days of the horse and cart.
The industry should face up to the this fact and provide the necessary features to allow safe towing under increasingly unfavourable weight ratio conditions. Electronic stabilisers and tyre pressure monitors should at least be available as factory-fitted options for caravans, just as ESP+ is becoming standard on many new cars. All these devices are readily available but the manufacturers seem to be hesitant to offer them. The car industry is making improvements but caravan chassis design hasn't advanced much since the days of the horse and cart.
Very true Lutz
As an aside in CC mag today it stated that BPW and Alko are both German based chassis manufacturers so I hope that they do not have ways of finding you !!!!
As an aside in CC mag today it stated that BPW and Alko are both German based chassis manufacturers so I hope that they do not have ways of finding you !!!!
For the sake of good towing stability, noseweight can never be too high. It is limited only by what the car, the towbar and the caravan's drawbar and coupling will take without danger of physical failure. All these figures must be available somewhere. The maximum permissible load on the towbar is plated. Usually this is the same as the limit for the car itself although it pays to check in the vehicle owner's manual. The same goes for the maximum noseweight applicable to the caravan.
If a hitch is almost scraping the tarmac, as you say, the owner has obviously not kept within the limits specified by the manufacturer.
I have no problems with discussing the subject with BPW or Alko. In fact, I have met their engineers at a recent exhibition. It does appear, however, that as long as there is not enough consumer demand for technical improvements, the chassis manufacturers have little incentive to become pro-active despite their awareness of new safety-related features.
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