MTPLM query

[Buckman]

If your caravan has a MTPLM of i.e. 1600kg and with a nose weight of 100kg, but actually weighs 1630kg when not connected to the car. If you then connected the caravan to the car, is the load on the caravan tyres then reduced by approximately 100kg resulting in the caravan being within its MTPLM?
I hasten to add that this is a scenario question as we are not over loaded and our nose weight is under 150kg.

 

[WoodlandsCamper]

The MTPLM is always the MTPLM, you cannot apportion it.

 

[Buckman]

The MTPLM is always the MTPLM, you cannot apportion it.

The MTPLM is only a guideline and you cannot be prosecuted for exceeding the MTPLM on the sticker on the side of the caravan however you can be prosecuted for exceeding the weight plate that is fixed to post 2012 trailers or the load rating of the tyres or where your trailer is a danger on the roads. Many trailers do not have a MTPLM sticker as it is not mandatory.

 

[ProfJohnL]

The MTPLM is the maximum permitted Mass of the whole solo caravan, and as such it includes any nose load.

The legal status of MTPLM was extensively discussed several years ago, and was eventually cleared up when an EU directive (and I can't remember its number or date) made it the case that where a chassis was supplied to another subsequent manufacturer who added and effectively completed the trailer (in our case the caravan manufacturer) the final manufacture could apply an MTPLM which de-rated the trailers maximum permitted mass to less than the axle manufactures load, and that the MTPLM would be used as the trailers MAM.

The Department for Transport stated in Nov 2009

"The weight capacity of the trailer
A trailer manufacturer must decide the Gross Vehicle Weight (GVW) of the trailer and mark it on the trailer chassis plate. This cannot be exceeded....This document is DfT's understanding of the law. Interpretation of the law is a matter for the courts. You are thus advised to consult legislation and, if necessary, seek independent expert (perhaps legal) advice. "

This is a similar process to the common practice in the haulage industry where a large trailers tend to have larger permitted masses, but some businesses may need the volume of a trailer but even when fully loaded with their products (low density items) the trailer potential weight carry capacity is not completely used up. The operator can apply for a lower "plated MAM" and thus it attracts less road funds taxation.

It is now compulsory for trailers to carry an easily visible weight plate which will show the MTPLM adn that figure will be used at road side checks for overloading etc.

 

[Martin24]

Check the max nose weight for the caravan not just your tow car maximum. Most 'vans have a maximum 100kg for nose weight.

 

[Buckman]

The MTPLM is the maximum permitted Mass of the whole solo caravan, and as such it includes any nose load.

The legal status of MTPLM was extensively discussed several years ago, and was eventually cleared up when an EU directive (and I can't remember its number or date) made it the case that where a chassis was supplied to another subsequent manufacturer who added and effectively completed the trailer (in our case the caravan manufacturer) the final manufacture could apply an MTPLM which de-rated the trailers maximum permitted mass to less than the axle manufactures load, and that the MTPLM would be used as the trailers MAM.

The Department for Transport stated in Nov 2009

"The weight capacity of the trailer
A trailer manufacturer must decide the Gross Vehicle Weight (GVW) of the trailer and mark it on the trailer chassis plate. This cannot be exceeded....This document is DfT's understanding of the law. Interpretation of the law is a matter for the courts. You are thus advised to consult legislation and, if necessary, seek independent expert (perhaps legal) advice. "

This is a similar process to the common practice in the haulage industry where a large trailers tend to have larger permitted masses, but some businesses may need the volume of a trailer but even when fully loaded with their products (low density items) the trailer potential weight carry capacity is not completely used up. The operator can apply for a lower "plated MAM" and thus it attracts less road funds taxation.

It is now compulsory for trailers to carry an easily visible weight plate which will show the MTPLM adn that figure will be used at road side checks for overloading etc.

You are confirming that the MTPLM sticker on the body of the caravan is not mandatory and also agreeing with my post that it is not a mandatory requirement or even legal. It is the plate on the chassis showing the GVW that is mandatory. I would be obliged if you could point me to the legislation where it even refers to MTPLM as I have not come across it yet.
I am not advocating that any one over load their caravan however I presented a scenario of a caravan on its own exceeding the MTPLM on the sticker by 30kg and if it is exceeds the MTPLM when it is hitched to the car. The DVSA will never ask you to unhitch the caravan from the car and will always weight the caravan while it is attached to the car. The question is the nose weight of the caravan transferred to the car resulting in the caravan then being within the MTPLM figure on the sticker. Note there is a big difference between the sticker which is not mandatory and the fixed plated on the chassis which is mandatory.
Remember this is a scenario and the question related to the transfer of weight and not the legalities as I am sure we are all aware of the legalities etc.

 

[Buckman]

Check the max nose weight for the caravan not just your tow car maximum. Most 'vans have a maximum 100kg for nose weight.

The nose weight on our (former) caravan is 140kg and within the limits of the BPW chassis.

 

[otherclive]

Check the max nose weight for the caravan not just your tow car maximum. Most 'vans have a maximum 100kg for nose weight.

The nose weight on our (former) caravan is 140kg and within the limits of the BPW chassis.

I read Prof John's post as effectively saying that the maker of the caravan can specify the MTPLM which then becomes the MAM of the "trailer". However, I suspect that VOSA checks would concentrate on axle plate load and tyre index load. I can't agree that VOSA don't unhitch the outfit. Mine was unhitched some years ago when a police motorcycle patrol escorted me to a VOSA station somewhere near Ringwood. Pleased to say all was within the law.

My last caravan and this one too have self adhesive weight/tyre detail plates that lost their readability within 2-3 years. I have obtained a replacement plate from Swift but have decided not to attach it to its normal outside spot but carry it within the caravan. Why it is beyond the wit of man to prove a plate that lasts for something like 10 years is beyond me. After all there are stickers all over the outside of aircraft that are readable and Im sure they last longer than 2-3 years even when pounded by rain and hail at 300mph plus.

 

[Raywood]

My understanding is that the MTPLM is the maximum weight and if you exceed this you can be prosecuted and I would not want to try and argue otherwise. In most cases the chassis manufacturer will have specified a different and higher weight but I doubt many magistrates would go along with a defence based on this assuming the caravan builder might have altered this in some way or there are other factors affecting the MTPLM. Looking under the caravan you will see that the chassis has various holes drilled in it, allowing the same chassis to be used at various lengths. I may be wrong but it could be this affects the load it can carry.
Most caravans can have their MTPLM uprated for free, or a nominal sum though so if you are likely to be over this, I would ask the manufacturer if this can be done but if not put a bit more in the car.

 

[Buckman]

Check the max nose weight for the caravan not just your tow car maximum. Most 'vans have a maximum 100kg for nose weight.

The nose weight on our (former) caravan is 140kg and within the limits of the BPW chassis.

I read Prof John's post as effectively saying that the maker of the caravan can specify the MTPLM which then becomes the MAM of the "trailer". However, I suspect that VOSA checks would concentrate on axle plate load and tyre index load. I can't agree that VOSA don't unhitch the outfit. Mine was unhitched some years ago when a police motorcycle patrol escorted me to a VOSA station somewhere near Ringwood. Pleased to say all was within the law.

My last caravan and this one too have self adhesive weight/tyre detail plates that lost their readability within 2-3 years. I have obtained a replacement plate from Swift but have decided not to attach it to its normal outside spot but carry it within the caravan. Why it is beyond the wit of man to prove a plate that lasts for something like 10 years is beyond me. After all there are stickers all over the outside of aircraft that are readable and Im sure they last longer than 2-3 years even when pounded by rain and hail at 300mph plus.

My guess is that the manufacturer knows the sticker is not mandatory and is only a guideline. The chassis plate over rides it anyway so why bother with a proper plate as most trailers would not have a stick on guideline anyway.
However we digress as the question is about whether part of the MTPLM is transferred to the car when the trailer is hitched to the car.

 

[WoodlandsCamper]

However we digress as the question is about whether part of the MTPLM is transferred to the car when the trailer is hitched to the car.

As stated to you before by various people the MTPLM is a fixed value and does not change. However when in use some of the mass of the van (ie noseweight) is carried by the tow hitch and the rest on the axle(s).

 

[otherclive]

Check the max nose weight for the caravan not just your tow car maximum. Most 'vans have a maximum 100kg for nose weight.

The nose weight on our (former) caravan is 140kg and within the limits of the BPW chassis.

I read Prof John's post as effectively saying that the maker of the caravan can specify the MTPLM which then becomes the MAM of the "trailer". However, I suspect that VOSA checks would concentrate on axle plate load and tyre index load. I can't agree that VOSA don't unhitch the outfit. Mine was unhitched some years ago when a police motorcycle patrol escorted me to a VOSA station somewhere near Ringwood. Pleased to say all was within the law.

My last caravan and this one too have self adhesive weight/tyre detail plates that lost their readability within 2-3 years. I have obtained a replacement plate from Swift but have decided not to attach it to its normal outside spot but carry it within the caravan. Why it is beyond the wit of man to prove a plate that lasts for something like 10 years is beyond me. After all there are stickers all over the outside of aircraft that are readable and Im sure they last longer than 2-3 years even when pounded by rain and hail at 300mph plus.

My guess is that the manufacturer knows the sticker is not mandatory and is only a guideline. The chassis plate over rides it anyway so why bother with a proper plate as most trailers would not have a stick on guideline anyway.
However we digress as the question is about whether part of the MTPLM is transferred to the car when the trailer is hitched to the car.

The answer is "no" MTPLM is a specified mass.

 

[Buckman]

However we digress as the question is about whether part of the MTPLM is transferred to the car when the trailer is hitched to the car.

As stated to you before by various people the MTPLM is a fixed value and does not change. However when in use some of the mass of the van (ie noseweight) is carried by the tow hitch and the rest on the axle(s).

I am sorry to disagree with the above statement otherwise you would not be able to upgrade the MTPLM if it was a fixed value. It is not illegal not to have the MTPLM sticker displayed on a caravan as it is not a statutory requirement. The weight plate on the trailer chassis is what counts.
After all however many trailers have a sticker on it using the MTPLM. I do not think that the words MTPLM are even used in any legislation as it seems to be confined to the caravan industry. I am not sure why every one is on about the MTPLM when the question is about the load being transferred to the vehicle? Surely a simple "Yes" or "No" about the load being transferred will suffice?

 

[WoodlandsCamper]

I give up trying to help you. bye bye.

 

[Buckman]

I give up trying to help you. bye bye.

I am sorry, how were you trying to help? If you cannot answer the question, not a problem as I do not know the answer either. No skin off my nose.

 

[otherclive]

However we digress as the question is about whether part of the MTPLM is transferred to the car when the trailer is hitched to the car.

As stated to you before by various people the MTPLM is a fixed value and does not change. However when in use some of the mass of the van (ie noseweight) is carried by the tow hitch and the rest on the axle(s).

I am sorry to disagree with the above statement otherwise you would not be able to upgrade the MTPLM if it was a fixed value. It is not illegal not to have the MTPLM sticker displayed on a caravan as it is not a statutory requirement. The weight plate on the trailer chassis is what counts.
After all however many trailers have a sticker on it using the MTPLM. I do not think that the words MTPLM are even used in any legislation as it seems to be confined to the caravan industry. I am not sure why every one is on about the MTPLM when the question is about the load being transferred to the vehicle? Surely a simple "Yes" or "No" about the load being transferred will suffice?

It seems to me that you know the answer to your question so why keep challenging the views of others without any substance in your comments. MTPLM is fixed by the maker. If the chassis can accept a higher payload you can pay to have it increased to a higher MTPLM. Is this any different to those who pass 70 years old and pay to have their 3500+kg motor home replated to 3500 kg? It's life and we have to deal with a certain level of inconsistency in our lives.

 

[Buckman]

However we digress as the question is about whether part of the MTPLM is transferred to the car when the trailer is hitched to the car.

As stated to you before by various people the MTPLM is a fixed value and does not change. However when in use some of the mass of the van (ie noseweight) is carried by the tow hitch and the rest on the axle(s).

I am sorry to disagree with the above statement otherwise you would not be able to upgrade the MTPLM if it was a fixed value. It is not illegal not to have the MTPLM sticker displayed on a caravan as it is not a statutory requirement. The weight plate on the trailer chassis is what counts.
After all however many trailers have a sticker on it using the MTPLM. I do not think that the words MTPLM are even used in any legislation as it seems to be confined to the caravan industry. I am not sure why every one is on about the MTPLM when the question is about the load being transferred to the vehicle? Surely a simple "Yes" or "No" about the load being transferred will suffice?

It seems to me that you know the answer to your question so why keep challenging the views of others without any substance in your comments. MTPLM is fixed by the maker. If the chassis can accept a higher payload you can pay to have it increased to a higher MTPLM. Is this any different to those who pass 70 years old and pay to have their 3500+kg motor home replated to 3500 kg? It's life and we have to deal with a certain level of inconsistency in our lives.

I never thought it was so difficult to get an simple straight answer to what I though was a a reasonable question. The question was never about the MTPLM. Maybe I should never have included "MTPLM". The question was whether any of the load of the trailer was transferred to the towing vehicle and absolutely nothing to do with MTPLM.
I will make it even simpler. A caravan or trailer has a gross vehicle mass of 1600kg with a nose weight of 100kg on the hitch of the trailer. How much of that mass is transferred to the towing vehicle when hitching up? Maybe I never put across the original question correctly and subsequently confused every one into offering well meaning advice that had nothing to do with the question.

 

[Raywood]

That is still not an easy to answer question. The basic answer is 100 kg when you hitch, although you can complicate that by saying this is only true if the level you hitch, is the level where the nose weight was measured.. Once you start moving the road undulations will add and subtract weight and towing will mean more weight is taken horizontally by the car either as it pulling or being pushed.

 

[otherclive]

I thought Woodlands Camper actually answered your question quite a few posts back. As said above the static nose weight is carried by the car and would deduct from the total weight of the caravan. But please don't reopen the debate on how to measure noseweight as there was a very long thread on the subject not long ago. Cheers

 

[ProfJohnL]

Hello Buckman,

In your last post

I never thought it was so difficult to get an simple straight answer to what I though was a a reasonable question. The question was never about the MTPLM.

Yet in you first post on this thread you stated

If your caravan has a MTPLM of i.e. 1600kg and with a nose weight of 100kg, but actually weighs 1630kg when not connected to the car. If you then connected the caravan to the car, is the load on the caravan tyres then reduced by approximately 100kg resulting in the caravan being within its MTPLM?
I hasten to add that this is a scenario question as we are not over loaded and our nose weight is under 150kg.

This thread clearly IS a question about MTPLM, and that is why most of us have responded accordingly with simple straight answers!

For clarity, the MTPLM is accepted by the authorities as the MAM for trailer, and if a caravan when weighed exceeds its MTPLM it will be classed loaded above its legal limit.

The MTPLM does include the entire weight of the solo caravan and its nose load. It has nothing to do with the load transfer to the tow vehicle. Regardless of how much nose load you create by adjusting the position of the internal load, the MTPLM is a specified limit by the trailer manufacturer. On a concurrent thread the reason for manufacturers applying a lower MTPLM is explained.

The MTPLM is the total maximum permitted of the solo caravan, and as such includes the load on the axle in addition to the proportion of the weight applied to teh tow coupling.

Nose load transference is used when it relates to the towing ability of the tow vehicle. The tow vehicle has a maximum towed weight limit. The key word is "towed" in other words the load carried by the trailers wheels. This excludes the nose load which is carried by the car and not towed. However this is precisely dependant on how you have loaded the caravan.

But returning to you last post

....I will make it even simpler. A caravan or trailer has a gross vehicle mass of 1600kg with a nose weight of 100kg on the hitch of the trailer. How much of that mass is transferred to the towing vehicle when hitching up? Maybe I never put across the original question correctly and subsequently confused every one into offering well meaning advice that had nothing to do with the question.

This is actually an entirely different question, but even here you are missing the important difference between weight limits and measured weights.

The Gross Vehicle Mass is the same as the MTPLM, and is a weight limit, not a measured weight.

So lets look at this in a slightly different way - from the tow vehicles point of view. What ever nose load you create (and don't forget this will change depending on how you load the caravan) the nose load is carried by the car not towed. The cars towed load is only the load actually carried by the trailers road wheels, and that value should not exceed the cars towed weight limit.

If we applied this to the figues you provided then of the 1600kg (Measured) weight of caravan with a 100kg nose load then 100kg would be carried and only 1500kg towed. But if of your 1600kg caravan you only had a nose load of 75kg, then 1525kg would be towed.

I am not going to spend time looking for the legislation you have asked be to provide, I suggest you look it up your self.

It is an EU requirement (Adopted by the UK) trailer manufactures must apply a data plate that includes the trailers Maximum Authorised Mass (MTPLM)

It is of course up to you if you choose to ignore this advice, and rather than simply repeating you dissension with the position we have suggested, perhaps you should provide the references that lead you to your contrary conclusions.

 

[Buckman]

Hello Buckman,

In your last post

I never thought it was so difficult to get an simple straight answer to what I though was a a reasonable question. The question was never about the MTPLM.

Yet in you first post on this thread you stated

If your caravan has a MTPLM of i.e. 1600kg and with a nose weight of 100kg, but actually weighs 1630kg when not connected to the car. If you then connected the caravan to the car, is the load on the caravan tyres then reduced by approximately 100kg resulting in the caravan being within its MTPLM?
I hasten to add that this is a scenario question as we are not over loaded and our nose weight is under 150kg.

This thread clearly IS a question about MTPLM, and that is why most of us have responded accordingly with simple straight answers!

For clarity, the MTPLM is accepted by the authorities as the MAM for trailer, and if a caravan when weighed exceeds its MTPLM it will be classed loaded above its legal limit.

The MTPLM does include the entire weight of the solo caravan and its nose load. It has nothing to do with the load transfer to the tow vehicle. Regardless of how much nose load you create by adjusting the position of the internal load, the MTPLM is a specified limit by the trailer manufacturer. On a concurrent thread the reason for manufacturers applying a lower MTPLM is explained.

The MTPLM is the total maximum permitted of the solo caravan, and as such includes the load on the axle in addition to the proportion of the weight applied to teh tow coupling.

Nose load transference is used when it relates to the towing ability of the tow vehicle. The tow vehicle has a maximum towed weight limit. The key word is "towed" in other words the load carried by the trailers wheels. This excludes the nose load which is carried by the car and not towed. However this is precisely dependant on how you have loaded the caravan.

But returning to you last post

....I will make it even simpler. A caravan or trailer has a gross vehicle mass of 1600kg with a nose weight of 100kg on the hitch of the trailer. How much of that mass is transferred to the towing vehicle when hitching up? Maybe I never put across the original question correctly and subsequently confused every one into offering well meaning advice that had nothing to do with the question.

This is actually an entirely different question, but even here you are missing the important difference between weight limits and measured weights.

The Gross Vehicle Mass is the same as the MTPLM, and is a weight limit, not a measured weight.

So lets look at this in a slightly different way - from the tow vehicles point of view. What ever nose load you create (and don't forget this will change depending on how you load the caravan) the nose load is carried by the car not towed. The cars towed load is only the load actually carried by the trailers road wheels, and that value should not exceed the cars towed weight limit.

If we applied this to the figues you provided then of the 1600kg (Measured) weight of caravan with a 100kg nose load then 100kg would be carried and only 1500kg towed. But if of your 1600kg caravan you only had a nose load of 75kg, then 1525kg would be towed.

I am not going to spend time looking for the legislation you have asked be to provide, I suggest you look it up your self.

It is an EU requirement (Adopted by the UK) trailer manufactures must apply a data plate that includes the trailers Maximum Authorised Mass (MTPLM)

It is of course up to you if you choose to ignore this advice, and rather than simply repeating you dissension with the position we have suggested, perhaps you should provide the references that lead you to your contrary conclusions.

Thanks to Raywood and Otherclive for the answer and confirm what I thought. Phew glad that is cleared up now. I just regret using "MTPLM" in my example as the seem to cloud the issue.

 

[Craigyoung]

I've been reading all the replies and cringing every time an argument starts people most cringe when they see this question come up every time!

 

[Martin24]

As WC says, goodbye. Just about all some people deserve.

 

[GD485]

I think the reason why a trailer manufacturer determines the MAM is it is they who make the body that support the load that is placed upon th chassis.
The rules are not meant just for caravan manufacturers they are for all trailers which could mean articulated trucks.
The chassis in most cases is an of the shelf item. The body builder will select the chassis nearest their need. This may have an axle load that is greater than the max load the body could carry.
In the world of caravans the MTPLM is the maximum gross weight of the whole vehicle. This maybe due to the axle load limit but often the load is determined by the marketing department wanting the caravan to fit in to a particular range in the market.
This is why individual customers can have their vans updated by the manufacturer issuing a new data plate.