Theoretical(ish) weights question

Sep 7, 2007
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Hi all

Have been looking a lot recently at discussion about weights etc. I like to try and understand everything to the nth degree just for my own peace of mind and idle curiosity.

So to put some of my numbers into the mix:

Current car is 2016 VW Touran 1.6 bmt
Kerb weight 1539 kg
Gross vehicle weight 2190kg (so a massive 651KG of payload!!!)
GTW 3720 KG

Currently I tow a Bailey ranger 550/6 @ MTPLM of 1326KG so just over the 85% “recommendation” but have been towing for >20years so I consider myself experienced and passed my test in 1993

Now all of the above I think I understand

Now here’s where I get a little confused

For my car GTW-GVW = 1530 KG. Is this set in stone assuming caravan is loaded to MTPLM and car is loaded to GVW or would sensible calculation provide a variance of both ultimately only a weighbridge could say for sure I guess?

Manual quotes 2 figures for trailer load limit:

1500KG @ 12% gradient
1800KG @ 8% gradient

Which figure should you go by or is it just common sense (again there is GTW and/or 85% to consider) and does this figure trump and calculation of GTW-GVW?

Lastly before I sign off as my brain is hurting now...

Assuming I went to the 1500/1800 KG (which I don’t intend to) the whole nose weight figure confuses me. Am I right in thinking that if I have a nose weight limit (according to VW) of 80KG does that mean that if the caravan weighs say 1540KG and its loaded such that nose weight is bang on 80KG then this 80Kg is considered to be part of the GVW of my car and not included in that MTPLM of the caravan?

Thanks in advance hopefully my post makes sense!
 
May 24, 2014
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Well, firstly dont try to overthink this because every vehicle will behave differently. There is a common saying, the 85% rule that isnt a rule but a sensible suggestion, and that is that your loaded caravan ideally wouldnt be more than 85% of the cars kerbweight. It should be noted that
THERE IS NO SUCH THING AS AN 85% RULE.
Certainly this is good for a novice driver. It also suggests that an experienced driver/tower would be ok running up to 100% of the cars kerbweight but I wouldnt recommend that.

The noseweight you mention does as far as I am aware not add to the cars GVW. What you will find is that your car will have a figure that states the maximum noseweight the car should take, if it is as you say 80kg, then loading your caravan as close to the 80kg noseweight should help for a stable tow. Too much noseweight will deflect your suspension downwards and make the towcar unstable and of course reduce traction on your front wheels. Too little noseweight and you may find a skittish caravan. You car will also be giving a figure of its maximum towabiltiy weight. I have often wondered where they get these figures from as my own vehicle has a KW of 2350kg and a max tow of 3.5 tonnes, somewhat more than the 85%.

The
1500KG @ 12% gradient
1800KG @ 8% gradient
that you mention is the cars ability to pull away on those gradients with the corresponding weight.
 
Mar 14, 2005
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tillboy said:
Hi all

Have been looking a lot recently at discussion about weights etc. I like to try and understand everything to the nth degree just for my own peace of mind and idle curiosity.

So to put some of my numbers into the mix:

Current car is 2016 VW Touran 1.6 bmt
Kerb weight 1539 kg
Gross vehicle weight 2190kg (so a massive 651KG of payload!!!)
GTW 3720 KG

Currently I tow a Bailey ranger 550/6 @ MTPLM of 1326KG so just over the 85% “recommendation” but have been towing for >20years so I consider myself experienced and passed my test in 1993

Now all of the above I think I understand

Now here’s where I get a little confused

For my car GTW-GVW = 1530 KG. Is this set in stone assuming caravan is loaded to MTPLM and car is loaded to GVW or would sensible calculation provide a variance of both ultimately only a weighbridge could say for sure I guess?

Manual quotes 2 figures for trailer load limit:

1500KG @ 12% gradient
1800KG @ 8% gradient

Which figure should you go by or is it just common sense (again there is GTW and/or 85% to consider) and does this figure trump and calculation of GTW-GVW?

Lastly before I sign off as my brain is hurting now...

Assuming I went to the 1500/1800 KG (which I don’t intend to) the whole nose weight figure confuses me. Am I right in thinking that if I have a nose weight limit (according to VW) of 80KG does that mean that if the caravan weighs say 1540KG and its loaded such that nose weight is bang on 80KG then this 80Kg is considered to be part of the GVW of my car and not included in that MTPLM of the caravan?

Thanks in advance hopefully my post makes sense!

Hello Tillboy,

I was just scanning my tablet as I went to bed, and I saw this new question from you. I note that Thingy has already responded, but I am concerned that the response does not answer your question, and the are some inaccuracies in his posting which could give you the wrong steer on the subject. I couldn't get it out of my head so I have started my computer to compose this missive.

It can seem that the question of towing weights is unnecessarily complicated, and as a consequence there have been a number of short cuts frequently used by caravanners. Most of these are perfectly legal becasue the outcome err on the right side of the law, but it does mean some of the finer points are not accurately described. You have also asked for details so you can hopefully gain a better understanding of the subject.

Lets get the 85% issue out of the way. I do not know why Thingy even hinted that its anything more than guidance, but that is all it is, but it is based on the understanding that in particular caravans are not easy towing trailers, they are far from perfect and do present some big challenges for cars and drivers. For that reason it is sensible to try to keep the weight and therefore size of a caravan as small as is reasonably possible. The industry somehow settled on 85% as the preferred figure, yet it offers no guarantees of good matching or safety.

Tow cars sold in the UK have been subject to the rigours of the EU Type Approval process, Part of this process requires the car manufacture to set
out the the cars maximum load bearing capacities which will include the solo car Maximum Authorised Mass (MAM = GVW), for a towing vehicle its combined MAM (= GTW), Its Maximum Towed load limit and the maximum static vertical nose load (S value). Each of these values are set in stone and must not be exceeded.

The maximum towed load limit is derived from the cars ability to start 5 times on a specified gradient. Generally this is a 12% gradient, but some manufacturers also include a higher limit for a less steep 8% gradient. These figures are limits and you would have to choose the one that suits your proposed route. However You correctly point out that many manufactures set their maximum towed load to be = GTW - GVW, That represents the maximum towed when the car is fully laden. In your case the manufacture has allowed a higher towed weight limit, provide the car is only partially laden and that the total weight of the combined outfit does not exceed the tow cars GTW limit.

I have specifically used the phrase "towed Load" rather than weight of trailer, becasue the towed part of a trailer is only the load carried on the trailers road wheels, it excludes the proportion of the trailer's weight (nose load) supported by the hitch of the car. This partially answers one of your specific questions about how the nose load is accounted for.

Whatever nose load is created by the trailer is applied to the cars hitch. This is no longer accounted for as part of the towed load, but it becomes part of the tow cars load. This must be accounted for in the cars loading. So for example if had a solo car that was loaded up to its GVW limit you could not then apply the nose load as it would exceed the cars GVW limit. so when considering towing you must keep some of the cars load capacity available to accommodate the caravan's nose load.

The other aspect of nose load is its not a fixed a variable, and it is determined by how you load the trailer. You must adjust the loading of the trailer to trim for your chosen nose load value. For your information The EU require car manufacture to rate the S value for the vehicles to be a minimum of 25Kg or at least 4% of the Towed weight limit. However the UK caravan industry suggest aiming for between 5 & 7 of the caravan's MTPLM.

And this brings me onto another or of Thingy's points. Technically the nose load of the trailer will act to unload the cars front axle, but the degree of the effect will be barely detectable provided the nose load is within the cars S value limit. In practice it will be less than having a front seat passenger or not. Suffice to say if you can detect it whilst driving, it must be grossly over the load limit for the vehicle.

Another often made mistake is the assumption that the trailers MTPLM must be no greater than the cars Maximum Towed Load. If this protocol is adopted, then the weights would be fully legal, but its not actually comparing apples with apples. The car is not interested in weight LIMIT of the trailer (MTPLM) its only interested in the physical weight it is trying to pull in other words the load on the trailers axle.

I hope this helps. Closed at 3:25 am!
 
May 24, 2014
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Hi Prof
I think you misread what I was saying
There is a common saying, the 85% rule that isn't a rule but a sensible suggestion,
I was suggesting that the terminology "other" people use is the 85% rule, I was stating that its not a rule, merely a suggestion or sensible guide.

Mind you, at 0325 hours, I guess even the Prof can appear mortal. Thought only the guilty or incontinent were awake then ;)

As for unloading the front axle, I agree its not a drastic thing, nevertheless it does occur and the effect greatly differs from car to car and suspension to suspension. As an example, a long estate car placing the towball further away from the rear axle would show a greater deflection than a 4x4 or saloon.
 
Nov 11, 2009
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Thingy said:
Well, firstly dont try to overthink this because every vehicle will behave differently. There is a common saying, the 85% rule that isnt a rule but a sensible suggestion, and that is that your loaded caravan ideally wouldnt be more than 85% of the cars kerbweight. Certainly this is good for a novice driver. It also suggests that an experienced driver/tower would be ok running up to 100% of the cars kerbweight but I wouldnt recommend that.

The noseweight you mention does as far as I am aware not add to the cars GVW. What you will find is that your car will have a figure that states the maximum noseweight the car should take, if it is as you say 80kg, then loading your caravan as close to the 80kg noseweight should help for a stable tow. Too much noseweight will deflect your suspension downwards and make the towcar unstable and of course reduce traction on your front wheels. Too little noseweight and you may find a skittish caravan. You car will also be giving a figure of its maximum towabiltiy weight. I have often wondered where they get these figures from as my own vehicle has a KW of 2350kg and a max tow of 3.5 tonnes, somewhat more than the 85%.

The
1500KG @ 12% gradient
1800KG @ 8% gradient
that you mention is the cars ability to pull away on those gradients with the corresponding weight.

Thingy,
Like a lot of real SUVs 4x4 your Shogun is designed as a working vehicle which comes equipped with low range gearbox, ability to lock the central diff, and probably diff locks too. As such it is capable of towing 3.5 tonnes but that may only be at low range speeds and not something as "frisky" as a caravan. My Disco 2, Pajero SWB and Sorento were all up in that range for maximum towing weight as all had the full 4x4 kit. That's why they come in so useful for removing ATMs from supermarket walls!
 
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Thingy said:
Hi Prof
I think you misread what I was saying........

Mind you, at 0325 hours, I guess even the Prof can appear mortal. Thought only the guilty or incontinent were awake then ;)

As for unloading the front axle, I agree its not a drastic thing, nevertheless it does occur and the effect greatly differs from car to car and suspension to suspension. As an example, a long estate car placing the towball further away from the rear axle would show a greater deflection than a 4x4 or saloon.

Hello Thingy, and top of the morning to you,

Over the years I have worked very hard to stop people misquoting the industry guidance, because it had become so ingrained in the caravanning world it was being used as if it had legal authority, and dire consequences. I have lost count of the number of those new to caravanning were making greater efforts to comply with the guidance than watching other more important legal or safety issues.

I take exception to any reference that even reinforces the phrase, even those who like you are actually pointing out its lack of authority. Its rather like the psychological test of associating words, certain links are deeply ingrained in our minds like salt and ______. Any reference using both words reinforces the memory of the phrase, so it's best to avoid any reference.

I will ask, you but I can't force you to edit both your posts to remove the ofending references.

Now to the second point, I can't deny the load on the tow ball will unload the front axle, and the degree will be affected by the distance from the hitch to the cars rear wheels, but the suspension makes no difference to the the forces which would be the the same, it's just that a soft suspension will travel more for the same applied force. And whilst this all sounds so dramatic, in practice if you do the maths (sorry Dacia) the effect is less than the effect of an adult front seat passenger. We don't hear of cars loosing control because there was no front passenger.

What can happen is tow vehicles can have more wheel spin when trying to pull away, and this is more prevalent with FwD model, and that is down to two things, the first is the extra inertia of the combination, and secondly the wheel torque which tries to lift the front of the car. These two things have much more impact than the nose load of the trailer, and actually as the caravan is accelerated the effect on the caravans center of mass will try to tip the caravan backwards and unload some of the nose load reducing its impact on the cars hitch.

So whilst the nose load does have an effect on the front axle load it's scale is very small and should not make any practical difference to normal drivers providing all the load limits have been followed.
 
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Thank you both profjohnl and thingy for your responses and further thanks to profjohnl for such a detailed reply right into the early hours I certainly hope you’re not suffering for it this morning!

Just a couple more points if I may:

If a driver were stopped for a vehicle check would voda/police just go by the weight plates on both car or caravan or would they actually weigh both.

In theory I don’t think I would ever get to my gross vehicle weight (even if I had the mother-in-law) in the car so would expect the actual gross to be lower. I imagine on the flip side though most caravans are loaded fairly close to ge MPLM so if I were concerned I guess moving some weigh into the car would be sensible.

Last thing (I think) as the manufacturer quotes a max towing weight (or in my case 2) would I be correct in thinking that the max MTPLM would be the lower of the manufacturer quoted max and the GTW-GVW?

Thanks again, I thought I understood this but it is easy to see why it is so confusing.

And just to clarify I intend to stick around the 85% “recommendation” as I believe it is sensible. I am hoping to upgrade my caravan next year but intend to upgrade my car when me lease expires prior.
 
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while it is true that the combination weights and ability to tow are quite complex it must be understood that this paper calculation may not be a true indication of the ability of a particular vehicle to do what it says is possible.

not all trailers are equal some are easy to tow others not so. caravans come in the not so category. as long as none of the legal maximums are exceeded the unit may be viable but unpredictable. suppose this is where the 85% recommendation comes from.

the key really is common sense. one could imagine towing a 1800kg boat and trailer but not a 1800kg van.
on the last point it is the actual weights of the unit not the paper weights that are checked unless your licence has restrictions post 94 then the paper weights are checked.
 
Nov 11, 2009
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tillboy said:
Thank you both profjohnl and thingy for your responses and further thanks to profjohnl for such a detailed reply right into the early hours I certainly hope you’re not suffering for it this morning!

Just a couple more points if I may:

If a driver were stopped for a vehicle check would voda/police just go by the weight plates on both car or caravan or would they actually weigh both.

In theory I don’t think I would ever get to my gross vehicle weight (even if I had the mother-in-law) in the car so would expect the actual gross to be lower. I imagine on the flip side though most caravans are loaded fairly close to ge MPLM so if I were concerned I guess moving some weigh into the car would be sensible.

Last thing (I think) as the manufacturer quotes a max towing weight (or in my case 2) would I be correct in thinking that the max MTPLM would be the lower of the manufacturer quoted max and the GTW-GVW?

Thanks again, I thought I understood this but it is easy to see why it is so confusing.

And just to clarify I intend to stick around the 85% “recommendation” as I believe it is sensible. I am hoping to upgrade my caravan next year but intend to upgrade my car when me lease expires prior.

When I was escorted to a VOSA weighbridge the car and caravan plates were examined and both were weighed.
 

Parksy

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I'm not sure exactly which 'dire consequences' have arisen from people incorrectly stating '85% rule' rather than correctly stating 'recommended 85% guideline' but I haven't read of any serious consequences on any caravan forum or publication, so perhaps you could provide evidence of these dire consequences Prof?
It is normally made quite clear on this forum that the 85% figure has no legal authority and Thingy pointed out that the 85% towing ratio is a sensible suggestion for those unfamiliar with towing a caravan, which it is.
Forum members can take exception to all sorts of things that appear on the message boards as we have seen time and time again, so let's allow others to express themselves in their own way.
 
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Im getting confused here ;)
Im saying exactly what Prof is saying, just in a different way. Many people will hear the mention of the offending 85% rule, but I was stating there really is no such rule. I have certainly not taken any exception to Profs comments, healthy debate is good and I do enjoy a good debate. I do take Profs point, and I will edit my post to suit. While I fully accept this supposed rule has been oft misinterpreted, there has to be a place to educate people by discussing why it shouldn't be taken verbatim. If we simply refuse to mention it, how can we then educate people that will hear it elsewhere.
Profs description of unloading the front axle is better than mine, but surely if its causing tyres to scrabble on a FWD car when pulling away, that is caused by a reducing of the available traction.

Otherclive
When talking of the weightwatchers (Parksy will be familiar with that term), was the weighing done on a full weighbridge or with the portable axle unit?
 
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Thingy said:
Im getting confused here ;)
Im saying exactly what Prof is saying, just in a different way. Many people will hear the mention of the offending 85% rule, but I was stating there really is no such rule. I have certainly not taken any exception to Profs comments, healthy debate is good and I do enjoy a good debate. I do take Profs point, and I will edit my post to suit.
Profs description of unloading the front axle is better than mine, but surely if its causing tyres to scrabble on a FWD car when pulling away, that is caused by a reducing of the available traction.

Otherclive
When talking of the weightwatchers (Parksy will be familiar with that term), was the weighing done on a full weighbridge or with the portable axle unit?

Full weighbridge near Ringwood. Full police motorcycle escort off of dual carriageway whilst heading east and then back down opposing carriageway to the vehicle checking area.
 
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They certainly meant to have you then, must have been either a quiet day or the chippy was in the same direction as the weighbridge.
Were you legal btw?
 
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Thingy said:
They certainly meant to have you then, must have been either a quiet day or the chippy was in the same direction as the weighbridge.
Were you legal btw?

I had no issues concerning the legality of the car or caravan. But they were painstaking not just on weights but MoT, licence, insurance, tyres on car and van, and noseweight re towbar etc. Didn’t offer a tea or coffee and this was before austerity bit :)

My luck too as in rural France I was stopped mid morning for a random breath test. Must be something about me?
 
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tillboy said:
Thank you both profjohnl and thingy for your responses and further thanks to profjohnl for such a detailed reply right into the early hours I certainly hope you’re not suffering for it this morning!

Just a couple more points if I may:

If a driver were stopped for a vehicle check would voda/police just go by the weight plates on both car or caravan or would they actually weigh both.

In theory I don’t think I would ever get to my gross vehicle weight (even if I had the mother-in-law) in the car so would expect the actual gross to be lower. I imagine on the flip side though most caravans are loaded fairly close to ge MPLM so if I were concerned I guess moving some weigh into the car would be sensible.

Last thing (I think) as the manufacturer quotes a max towing weight (or in my case 2) would I be correct in thinking that the max MTPLM would be the lower of the manufacturer quoted max and the GTW-GVW?

Thanks again, I thought I understood this but it is easy to see why it is so confusing.

And just to clarify I intend to stick around the 85% “recommendation” as I believe it is sensible. I am hoping to upgrade my caravan next year but intend to upgrade my car when me lease expires prior.

Good morning, I think I'm good to go well at least to my bath chair :unsure:

What information the authorities will use will depend on their reason for inspecting you or your vehicle.

So for example if they suspect a vehicle is over weight the only way they can test the suspicion is by weighing the vehicle, and comparing the results to the vehicle data plates. By passing a vehicle over a weighbridge, they can test for GTW, GVW, axle loads
and by measuring the solo car by calculation the can derive the caravans gross weight, and nose load.

If they are suspicious about the driver's licence entitlements, they only have to look at the data plates, because entitlements always look at the vehicles capacities not actual measured weights.

If in the opinion of an enforcement officer a vehicle has an unsafe load, neither compliance with licence or weight limits is a guaranteed excuse. Or like Otherclive you can be a totally suspicious looking character and they will check everything

When it comes to loading close to limits, I do agree that most caravans will be surprisingly close to their MTPLM because the loading margin is quite small, all the small bits and pieces do add up. When it comes to cars, there can be a considerable difference in pay load margins, but as with the caravan it can be surprising how much you do use, and of course don't forget the caravans nose load needs to be accommodated within the cars GVW. In the context of caravan weight checks by the authorities, in many case where they have detected a minor weights discrepancy, they may warn the driver and a give them the opportunity to re distribute the weight between car and caravan before being allowed on their way. If a driver does not have the correct licence, they will almost always prosecute, as there is no question about it. They will only be allowed on their way if a driver with the correct licence and insurance can drive the outfit, or otherwise the caravan will need to be unhitched and just the solo car can proceed.

Towed weights - This is the most confusing and even grey area of your question.
Let's review what the MTPLM of a trailer is. It is a weight limit not a measured weight, and it relates to the entire caravan not just the load on it road wheels. algebraically:-

Nose load + Axle load = Caravans Total Weight, which must be within the MTPLM limit.

It follows that provided a trailer has not been over loaded and there is a nose load, the MTPLM will always be bigger than the axle load.

But from the cars perspective the only towed load it sees, is the axle load of the trailer, as such the MTPLM of the trailer is of no relevance, its just the actual weight on the trailers road wheels.

The Towed weight limit is set by the manufacturer and you can choose which ever value that matches you journey, but you should keep documented evidence of the manufacturers statement with you in case you are stopped and the authorities question the fact you have a towed weight that exceeds GTW - GVW.

With the Tiguan and caravan you should not be contemplating going anywhere near the manufactures stated towed load limits.
 
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Prof,
I think Tillboy has a Touran, not a Tiguan!

Re the check that I was requested to attend, the examiners looked closely at the caravan tyres, which for 99.5% of outfits would have much more than the legal trade depth. Whilst there is no legal "use by date" on tyres, what they were keen to ascertain was the Load Index of the tyres to see if it was compatible with the caravans weight, and their visible condition. Tyre pressures on the van/car were not checked. Although I am sure that if they had any concerns the tyre pressures would have been included.
 
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Thingy said:
...
Profs description of unloading the front axle is better than mine, but surely if its causing tyres to scrabble on a FWD car when pulling away, that is caused by a reducing of the available traction.

That not quite correct,

Its the case that most cars are quite capable of spinning their driven wheels because there have more torque at the wheels than the surface friction and grip can withstand.

Let us assume a solo car can achieve an acceleration of 0.25G or 2.45M/S/S before the wheels start to scrabble. assuming the car weighs 1.5Tonnes using Force + Mass x Acceleration that gives us a maximum tractive force of 3678 Newtons

Now lets add a caravan into the mix so the mass is 2.7 tonnes, the rate of acceleration that can be achieved using the same tractive force of 3678N would only be 1.36M/S/S or 0.133G which is much less

The driver will sense this is slower adn will increase the throttle which increases teh torque at the driven wheels above teh grip threshold an the wheels will scrabble. This is the principle reason for wheel spin, in these circumstances not the small degree of reduced load becasue of the nose load from the trailer.
 
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ProfJohnL said:
Thingy said:
...
Profs description of unloading the front axle is better than mine, but surely if its causing tyres to scrabble on a FWD car when pulling away, that is caused by a reducing of the available traction.

That not quite correct,

Its the case that most cars are quite capable of spinning their driven wheels because there have more torque at the wheels than the surface friction and grip can withstand.

Let us assume a solo car can achieve an acceleration of 0.25G or 2.45M/S/S before the wheels start to scrabble. assuming the car weighs 1.5Tonnes using Force + Mass x Acceleration that gives us a maximum tractive force of 3678 Newtons

Now lets add a caravan into the mix so the mass is 2.7 tonnes, the rate of acceleration that can be achieved using the same tractive force of 3678N would only be 1.36M/S/S or 0.133G which is much less

The driver will sense this is slower adn will increase the throttle which increases teh torque at the driven wheels above teh grip threshold an the wheels will scrabble. This is the principle reason for wheel spin, in these circumstances not the small degree of reduced load becasue of the nose load from the trailer.

On dry roads with four passengers and suitcases my car doesn't loose traction on its front wheels when driving normally. With the caravan hitched up and the car loaded it will momentarily loose traction (felt rather than effect) until the Haldex clutches in and directs torque to the rear wheels too. Yet when loaded as an outfit the car has less weight in it than if I carry four passengers and suitcases.

PS edit Forgot to mention it only started to lose traction intermittently for a fraction of a wheel rotation after changing tyres from bidirectional Pirelli to very unidirectional Michelins. All other things about the outfit being equal.
 
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Whether the tyres scrabble because of poor road road service or too much torque at the front wheels, it still stands that a loss of traction is occurring. Am I not right in thinking that traction is created by the materials involved and the downward pressure on the surface of those materials. By the fulcrum effect, anything severely deflecting the rear suspension downwards has to have an effect on the loads on the front axle. Accepting that anything severely deflecting the rear suspension is either seriously overloaded, or the suspension is shot.

However, we are getting way away from the realms of the OPs question and in fairness, Prof has more than covered it with his detailed answers.

Of course, scrabbling the front tyres could just be sign of poor driving. Right thats me, Im off to find my tin hat :cheer: :p
 
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This and the other weight related thread contain enough data to become an Open University degree course. :p
If I was a newbie I may well have defected to Practical Motorhome :(
As expected the Prof has given an excellent technical paper and indeed Thingy has tried hard although criticised for quoting misnomers. Mmm. Debatable perhaps. No milencos for either I fear :whistle:
When I started tugging 40 years ago the gurus of the day were very particular about weight ratios and more importantly correct loading and nose weights/ load. Cars were smaller, less powerful as were caravans.
As and when similar discussions start again, which they will, please will correct loading be included and some assurance that phrases like “serious erosion” “ no such thing as a safe tow” etc are translated into more positive statements rather than the negativity which is clearly deterring newbies B)
 
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Perhaps, to put things into perspective, the 85% 'rule' or recommendation or whatever you want to call it is unheard of on the Continent and yet I have never seen noticeably more caravans littering the roads there than in the UK.
 

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