Caravan MTPLM

[Lutz]

I dont understand your piont concerning tyre index? your van was upgraded to 1400kg and the tyres were rated at 1420kg togeather. what was the problem. my bustner which had a max of 1500kg came new from germany with tyres rated to 750kg each.so equaled the 1500kg max of the caravan.....

In Germany, the load rating of caravan tyres can actually be up to 10% less than the weight of the caravan. This is because tyres normally have an N (=140km/h) speed rating, already giving a 40% safety margin over the legal maximum speed. This is considered to adequately compensate for the higher load. That's probably why the Bürstner was fitted with tyres rated as mentioned.

 

[JTQ]

In Germany, the load rating of caravan tyres can actually be up to 10% less than the weight of the caravan. This is because tyres normally have an N (=140km/h) speed rating, already giving a 40% safety margin over the legal maximum speed. This is considered to adequately compensate for the higher load. That's probably why the Bürstner was fitted with tyres rated as mentioned.

That stacks with the tyres on my Hymer which dont have a 10% Load Rating margin; though they are up to both its axle and total mass plating.values.
They have an "R" speed rating [170 km/h] so giving a massive 70% margin on that feature.
Strange that the British Tyre Makers Association take a different view and also IMO worrying they don't confidently stand by their own published tyre ratings.

With the possibility then of German vans having Load Ratings, albeit at speeds way above legal limits, that could be below the axle rating, what is likely to be VOSA stance if stopped?.

 

[otherclive]

I think that Uk tyre load ratings can be considered suitable but the margin helps to maintain some additional safety for those who overload their vans and maybe when overseas in hot climates tend to maintain higher speeds than in UK. The cost of my higher LI tyres was marginally more expensive than for the original LI tyres so maintains a safety margin is not a significant cost driver in the overall cost of ownership and usage.

 

[hortimech]

Hello, with all the discussion about MTPLM, I thought that I would email VOSA and try and get the definitive answer, the first question I asked was:

Would I be correct in saying that the GVW/GVM is calculated by adding AXLE 1 weight and AXLE 2 weight together?

The answer I got:

You are correct in that the basis of the calculation is -- the front axle weight is added to the rear axle weight which the gives the Gross Vehicle Weight.

I then asked about the sticker by the door and the data stamped into the chassis:

A caravan has (usually) a sticker affixed to it that gives its MTPLM and there is also stamped into the chassis a GVW. the MTPLM is usually less the GVW. Which would take precedence, the MTPLM or the GVW? For instance, if towing with a vehicle that had a towing limit of 1600kg and the MTPLM was 1400kg but the caravan actually weighed 1450kg, would it still be legal if the stamped in GVW was 1600kg?

The answer:

The Manufacturers Plate listing the caravans Gross Vehicle Weight and Axle/s weight is the one that stands up in law.

None of the plated weights for both towing vehicle and trailer can be legally exceeded i.e. axle weights, gross weights or train weight.

All the other weights/ratios do not have a legal basis in UK law other than the combination can not be operated/loaded in a dangerous manner.

So the caravan and trailer associations have best practice guides which virtually guarantee the legality of the rig when loaded.

Don't forget that some of the trailers mass will be 'carried' by the towing vehicle on its tow hitch and rear axle. This tends to vary between 50kg and 150kg depending on the vehicle/caravan.

So from this it would seem that VOSA do not bother with MTPLM and only worry about GVW, GTW and axle weights.

 

[Gafferbill]

The reply from VOSA is of course correct but please note the three terms below have all been used to describe the same thing and have the same meaning.........

GVW or Gross Vehicle Weight
- The weight of the vehicle laden to its maximum, as defined by the
vehicle manufacturer.

MAW or Maximum Authorised
Weight - The maximum weight for which the caravan is designed for normal use when being used on a road
fully laden. This must never be exceeded.
Sometimes also known as Maximum Gross Weight which usually applied to older models .......more recent
ones use the term Maximum Technically Permissible Laden Mass instead.

MTPLM or Maximum
Technically Permissible Laden Mass - As stated by the
vehicle manufacturer. This mass takes into account specific
operating conditions including factors such as the strength of
materials, loading capacity of the tyres etc. As such, it is the
heaviest condition at which the vehicle should ever be
operated.

 

[hortimech]

You are still missing the point, vosa said this:

The Manufacturers Plate listing the caravans Gross Vehicle Weight and Axle/s weight is the one that stands up in law.

MTPLM, MAW etc have NO standing in law only GVW has, this is straight from the mouth of the people likely to prosecute you if you get it wrong.

 

[Lutz]

I find VOSA's reply misleading. For a start, the GVW is NOT necessarily the addition of the maximum front and rear axle loads. The sum of the two can actually be higher than the GVW. In that case, one can only make full use of one of the two axle load limits, but never both at the same time.
They have also not clearly stated which manufacturer they are referring to when they say "The Manufacturers Plate listing the caravans Gross Vehicle Weight and Axle/s weight is the one that stands up in law." My interpretation is that they mean the caravan manufacturer, not the chassis manufacturer, as he is the last in the line. Otherwise, they should have written "The Manufacturers Plate listing the chassis Gross Vehicle Weight and Axle/s weight is the one that stands up in law."
Actually, although you are correct in saying that the law uses the term GVW, you will find that it also references MTPLM in later amendments. GVW and MTPLM are therefore interchangeable and have equal legal significance. The Directgov and DfT websites, which are also government institutions, just like VOSA, use the term MAM (Maximum Allowable Mass). VOSA have used the term GVW without disqualifying the other terms with the same meaning, just as practically everyone uses the term "kerbweight" although this is not a legal term.
I think you are interpreting more out of the VOSA reply than what they actually wanted to say, maybe due to their ambiguous choice of words.

 

[hortimech]

Ok, I can see where you are coming from, my understanding was that whatever plate gives the GVW and axle weight is the one that counts, the MTPLM weight is not recognized by law. Anyway, I have sent the gentleman at VOSA another email to try and get him to clarify the situation, when I get a reply, I will post it here.

 

[Lutz]

Ok, I can see where you are coming from, my understanding was that whatever plate gives the GVW and axle weight is the one that counts, the MTPLM weight is not recognized by law. Anyway, I have sent the gentleman at VOSA another email to try and get him to clarify the situation, when I get a reply, I will post it here.

Why, if the Vehicle Construction & Use Regulations refer to MTPLM do you consider MTPLM not to be recognised by law?
Besides, it would be illogical to disregard the weight limit placed on the caravan by the caravan manufacturer and consider only that of the chassis supplier. The GVW of the chassis is specified without consideration of its future use. The same chassis could be used for a low loader trailer and for a caravan, but it may well be sensible to restrict the weight limit for a caravan to a lower figure on account of the specifics of its construction.

 

[hortimech]

Why, if the Vehicle Construction & Use Regulations refer to MTPLM do you consider MTPLM not to be recognised by law?

Ok, When I say law, I mean what does VOSA understand to be the law.

Besides, it would be illogical to disregard the weight limit placed on the caravan by the caravan manufacturer and consider only that of the chassis supplier. The GVW of the chassis is specified without consideration of its future use. The same chassis could be used for a low loader trailer and for a caravan, but it may well be sensible to restrict the weight limit for a caravan to a lower figure on account of the specifics of its construction.

If you get pulled up to have your weight checked, there is a very good chance that VOSA will be involved and I want to be singing from the same hymn sheet as VOSA, not what any Tom, Dick or Harry is singing.

 

[Lutz]

If you get pulled up to have your weight checked, there is a very good chance that VOSA will be involved and I want to be singing from the same hymn sheet as VOSA, not what any Tom, Dick or Harry is singing.

I hardly think that the DfT can be described as Tom, Dick or Harry. Their information regarding the validity of plated weight data on a multi-stage build is quite explicit and logical to me. If VOSA interpret the law any other way, then there is obviously a disconnect between two government departments which one would have every right to challenge.

 

[Surfer]

You are still missing the point, vosa said this:

The Manufacturers Plate listing the caravans Gross Vehicle Weight and Axle/s weight is the one that stands up in law.

MTPLM, MAW etc have NO standing in law only GVW has, this is straight from the mouth of the people likely to prosecute you if you get it wrong.

I have been arguing this point for some time, but it appears both VOSA and myself are wrong according to some intellects on thsi thread who interpret the law to suit themselves! I have never agreed with exceeding the MTPLM of a caravan and have made that clear on numerous occasions. My argument always referenced the legality of term MTPLM.

 

[Gafferbill]

Ok, I can see where you are coming from, my understanding was that whatever plate gives the GVW and axle weight is the one that counts, the MTPLM weight is not recognized by law. Anyway, I have sent the gentleman at VOSA another email to try and get him to clarify the situation, when I get a reply, I will post it here.

.........I hope VOSA reply to you and that you post the reply on this tread.

I predict they will say that......... MTPLM is just a modern term for GVW and that the caravan manufacturer stipulates this figure not the chassis builder and that this is the legal maximum weight of the caravan.

 

[Lutz]

I can't see why you have such a problem with the term MTPLM. GVW is simply the original (old) term. MTPLM was added when EU Directives were incorporated in UK Construction & Use Regulations. The wording of the law, however, has not yet been updated in line with the Directives, even though the appendices to later amendments refer exclusively to MTPLM. I think there is no denying that the EU Directives, once ratified by the UK government, are just as legally applicable and as older requirements.
Reading your reply and some other literature, one gets the impression that MTPLM, whether a legally recognised term or not, applies only to caravans. That is not correct. It applies equally to all motor vehicles, as well.