Weights

[Jonathan_374528688]

hello thank you for reading this, Firstly i have a 3.5t licence as i passed after 97" , now i spoke to the dvla that said as long as the car is heavier than my caravan and does not weigh more than 3.5 in total im fine. now i know what weight my caravan is, but what is it on the car that makes the rest of the weight up, is it the kerb weight,,

so do i go by the kerbweight and the caravan weight to get my total without passengers / fuel and load etc

 

[SteveW77]

As far as the license is concerned, it is the total all up weight that must be under 3.5 tonnes. It doesn't matter how you split it, if the total is over 3.5tns then you are illegal.

Steve W

 

[602]

Hi.

Disagree.

The plated weight (MGW, MAM, or WHY) of the caravan must not exceed the UNLADEN (not KERB) weight of the tow car. The combined actual weight must not exceed 3500kgs.

The only exception is that you may tow a trailer weighing no more than 750kg, even if the combination then weighs more than 3500kgs.

Ducks head to avoid flack.

602

 

[ProfJohnL]

Hello Jonathon,

Sadly Steve's answerer is not quite right. Your licence restriction refers to the combined MAM's of both the trailer and the tug must not exceed 3500Kg. MAM stands for Maximum Authorised Mass, and is the maximum weight that the vehicle (or trailer and is equivalent to the MTPLM) is designed to be when fully loaded.

Even if your outfit actually weighs less than 3500Kg, if its maximum limits added together exceed 3500Kg it is illegal.

The other aspect of your licence that must not be ignored, is that the MAM of the trailer must not exceed the unladen weight of the tug (i.e. towing ratio must be less than 100%). (Trailer MTPLM)/Tugs Kerbweight) x 100%

Again these limits are based on specifications and not actual measured weights.

A good site to view is:

http://www.iwt.co.uk/brochures/ltt.pdf

 

[602]

Hi,

Check out

http://www.direct.gov.uk/en/Motoring/DriverLicensing/WhatCanYouDriveAndYourObligations/DG_4022547
You will see under Class B licence entitlement, that they refer to UNLADEN weight of the tow car, not the kerbweight.

If you have a modern car, this should be shown on your V5 under MIRO (Mass In Running Order). Presumably, for older vehicles, like what I drive, they will have to put it on a weighbridge. ???

I guess the ideal towcar will have a ULW of 1750kg, so it can tow a trailer of the same MAM. No, thats not right, cos you will have to deduct the weight of any passengers in the car, from the trailer. Golly gosh, they make it difficult.

602

 

[602]

Hi,

Question, can a class B licence holder fit L plates, and drive a 3500kg plus rig, if accompanied by a B+1 licence holder?

602

 

[Lutz]

The difference between kerbweight and unladen weight is that unladen weight, according to the directgov website does not include fuel whereas kerbweight is normally understood to include a full fuel tank.

This, again, is different to MIRO, which includes a 90% full fuel tank plus 75kg for the driver and miscellaneous items.

The V5c certificate will show MIRO, but calls it Mass in Service. This is, strictly speaking, neither unladen weight nor kerbweight.

 

[602]

Hi Lutz,

So where exactly do you look to find the Unladen Weight referred to in the DVLA driver's website? Even if you have told me already, please tell me again.

Personally, I would expect it to be a vehicle with FULL amount of fluids, and tools supplied by the manufacturer, clean and ready to roll. But then you get individual items, like a tow-bar, so where do they come into the equation?

The crazy thing is that they seem to suggest that the heavier your tow car is, the more it can tow safely ...... until you suddenly reach the point where the heavier your car, the less it can tow. And for some reason, this point is somewhere close to our desired targets.

It might make sense if carrying a few more passengers allowed you to tow a heavier trailer. Surely there is a better way, which is also easier to understand?

I feel the easiest way is to buy your car and caravan, then ask if you are allowed to drive it.

602

 

[SteveW77]

As the OP mentioned a caravan, and I know of no caravan that weighs 750kg or less, then as far as I can see what I said is valid, if the all up weight is above 3500kg then his license will not cover it.

Steve W

 

[Lutz]

You can find the official definition of unladen weight by clicking on the link included in my previous reply. It states quite clearly that fuel is NOT included.

Unless you have your V5c certificate revised to reflect a change in MIRO (or kerbweight) due to having a towbar (or anything else) fitted after the vehicle was first registered, the weight of such components must be deducted from the available payload. Consequently they do not influence your towload limit, but just reduce the remaining available payload.

There is a difference between what your driving licence allows you to tow and what the car is technically allowed to tow. The former is governed solely by the unladen weight of the towcar, the maximum permissible weight of the caravan and the maximum permissible total weight of the combination.

The technical limit, on the other hand, is specified by the car manufacturer and is determined by the maximum gross vehicle weight of the towcar, its maximum permissible gross train weight and its maximum permissible towload. Very often, the latter is simply max. GTW minus max. GVW, but not always (notably Renault). Only in such exceptional cases does the actual weight of the towcar have any influence on what you are allowed to tow.

 

[ProfJohnL]

As the OP mentioned a caravan, and I know of no caravan that weighs 750kg or less, then as far as I can see what I said is valid, if the all up weight is above 3500kg then his license will not cover it.

Steve W

Hello Steve,

I challenged your first answer because "The all up weight" has no definition. To me it meant the actual weight of the outfit, where as the licence restriction referees to the Maximum Authorised Mass.

It is quite conceivable to have an outfit where the combined MAM's exceed 3500Kg, but the actual all up weight in use is less than 3500Kg (i.e. not loaded to the limits). Such an outfit is illegal on a post Jan 1997 licence.

And the 'split' is also important, as the trailer MTPLM must not exceed the unladen mass of tug.

So the advice you offered is potentially misleading

 

[602]

Hi Steve W.

I believe that Freedom do an economy model, which doesn't have brakes, which implies that its MGW is under 750kg. Probably not a lot of people NEED to know that, but it might be of interest to those who have a B licence, and ......

Have a tow car with an MGW between 2750kg and 3500kg. OR

Have a tow car with a ULW less than 750kg. A B licence allows you to tow up to 750kg regardless of weight of tow car (at least, I think that's what it says). The problem is finding a sub-750kg car with manufacturers aproval to tow that weight. I'm not sure about cars built before they invented towing limits. Also, if the tow car is that light, the trailer will need brakes. So that knocks the Freedom off that shopping list.

The Freedom may INTEREST truck drivers who want a caravan to tow behind their on-the-limit truck.

602

 

[Lutz]

John, it is my understanding that where the Directgov site refers to, quote:"

 

[ProfJohnL]

Hello Lutz,

Your example concurs with my understanding of the regulations.

It is possible to have a tug that has a rated Gross Train Weight that is greater than 3500Kg, but provided the MAM of the tug and the MAM of the trailer is less not greater than 3500 it is alright for a post

 

[SteveW77]

it is my understanding that where the Directgov site refers to, quote:"The total weight of the vehicle and the trailer together can't weigh more than 3,500 kg.", they mean the MAM of the actual combination in question, not the plated maximum permissible gross train weight

It would be much simpler if they said what they meant, or do I mean meant what they said, It's now as clear as mud to me.

Steve W

 

[Lutz]

To complicate matters further, I believe VOSA now interpret the term 'unladen weight' to concur with the EU definition of MIRO (or Mass in Service, as the V5c certificate calls it) even though UK law, which was written before EU Directives came into effect, has not yet been brought into line to reflect the changes in definition.

 

[602]

Hi,

Looking at the DVLA website mentioned a few mails ag0, I see.....

B

Motor vehicles with a MAM of up to 3,500 kg, no more than eight passenger seats, with or without a trailer - weighing no more than 750 kg

17*

B

As category B but with a trailer weighing more than 750 kg. The total weight of the vehicle and the trailer together can't weigh more than 3,500 kg. The weight of the trailer, when fully loaded, can't weigh more than the unladen weight of the vehicle

Taking the top one first, I think it says that you can drive a 3500kg MAM vehicle plus a trailer up to 750kg.

The second paragraph say that if the trailer weighs more than 750kg, by which I presume they mean a MAM of over 750kg (???) then the tow car must weigh more, unlasen, that the MAM of the trailer. And because the trailer has an MAM in excess of 750kg, you cannot tow it if the combined MAMs exceed 3500kg.

Somebody should produce an idiot sheet (aka Logical Tree)to make life easier for Class B licence holders.

'Does trailer weigh more than 750kg?' If YES go to 'Does car weigh more than ........'. No! Sorry! My brain hurts. Not impossible, but I can't be bothered. Maybe after Xmas.

602

 

[ProfJohnL]

Hello 602,

I can't explain the reasoning behind the way the categories are set up, but its some witches brew from many years ago, and probably outdated, BUT unlike the caravan industries self appointed 85% for towing and 7% nose guidelines, the VOSA and DVLA are rules and carry sanctions if they are broken and detected.

The other point to remember is that the limits refer to the licence, not to the vehicles, so they are a paper exercise and not designed to from a mechanical stand point.

I think I detect some reasoning behind the 750Kg trailer issue. Trailers over 750Kg have to be braked. Those under 750 are not required to have overrun brakes.

Not to put a too finer point on it, if your tug can be 3500Kg, then it is most likely the brakes that will cope with the extra 750Kg.

A previous contributor (Timothy) pointed out the Ifor Williams website and a very useful decision flow chart

http://www.iwt.co.uk/brochures/ltt.pdf
It does make the decision process quite straight forward.

 

[ProfJohnL]

it is my understanding that where the Directgov site refers to, quote:"The total weight of the vehicle and the trailer together can't weigh more than 3,500 kg.", they mean the MAM of the actual combination in question, not the plated maximum permissible gross train weight

It would be much simpler if they said what they meant, or do I mean meant what they said, It's now as clear as mud to me.

Steve W

Hello Steve,

I have looked at the DirectGov web site, and it it does say what it means. It refers to the MAM, and goes on to describe what that includes.

I do concede it is a mine field but with a little persistence it does begin to make sense.

The biggest problem seems to be the myriad of ways that a particular weight or mass is described by different organisations. You do have to be on your toes as some measures seem as though they should be the same, but are subtlety different often with good reason.

 

[joeby]

lost me

 

[Lutz]

If you're lost, maybe you are towing an illegal oufit. How can you be sure you aren't?

 

[ProfJohnL]

Hello Joby,

Very seriously tell us were you 'got lost' and we will try to re-explain it to help you.

It does at time appear complex, but with a little perseverance it can become clear, and as Lutz writes you will then know if you are legal or not.