Technical Towing Weights on a BMW 125D

May 27, 2020
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Hi all

So unfortunately this week my trusty 54-plate Audi A3 has been written off (non-fault accident) - this was the vehicle we used for towing our small 2 berth caravan. I'm absolutely gutted as it had taken us 80k miles in 5 years all over the UK on camping adventures :(

Anyway, we also have a BMW 125D, however I need some technical perspective on the feasibility of towing with it.

Our caravan has a MIRO of 1085kg. It has an MLTPM of 1260kg. The car has a braked towing capacity of 1200kg and a kerbweight of 1565kg. On the face of it, I thought the car would not legally be allowed to tow the van due to the MLTPM, however my understanding is that when the van is attached to the car the nose weight is transferred to the car, therefore the towing weight is less, and therefore could be under the 1200kg.

I have a public weighbridge round the corner from me so am going to take the van there for some measurements attached/detached from the car.

Am I right in my logic/thinking that if the van is under 1200kg when attached to the car then it is perfectly acceptable (and legal) to tow with our BMW, despite it potentially weighing more than that when it is not attached to the car?

Thanks in advance for all your help.
 
Jul 18, 2017
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It is the maximum train weight that counts i.e. the sum to MTPLM and gross maximum weight of the car. BTW if going to the weigh bridge and you are stopped, you will be fined a dn points on your licence and you will not be able to continue your journey. In addition, you will only have third party cover if you exceed the maximum train weight of the towing vehicle and you could have mishapon the way to the weigh bridge. I would not chance it!
 
Nov 11, 2009
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Hi all

So unfortunately this week my trusty 54-plate Audi A3 has been written off (non-fault accident) - this was the vehicle we used for towing our small 2 berth caravan. I'm absolutely gutted as it had taken us 80k miles in 5 years all over the UK on camping adventures :(

Anyway, we also have a BMW 125D, however I need some technical perspective on the feasibility of towing with it.

Our caravan has a MIRO of 1085kg. It has an MLTPM of 1260kg. The car has a braked towing capacity of 1200kg and a kerbweight of 1565kg. On the face of it, I thought the car would not legally be allowed to tow the van due to the MLTPM, however my understanding is that when the van is attached to the car the nose weight is transferred to the car, therefore the towing weight is less, and therefore could be under the 1200kg.

I have a public weighbridge round the corner from me so am going to take the van there for some measurements attached/detached from the car.

Am I right in my logic/thinking that if the van is under 1200kg when attached to the car then it is perfectly acceptable (and legal) to tow with our BMW, despite it potentially weighing more than that when it is not attached to the car?

Thanks in advance for all your help.

This one has been debated a number of times before. You are correct in that noseweight transfers to the car which reduces the load on the caravan axle, but train weight is unchanged. As long as you stick within the cars legal towing limit, gross vehicle weight, axle loads, and train weight why not just take 60+ kg out of the caravan and into the car.
 
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This one has been debated a number of times before. You are correct in that noseweight transfers to the car which reduces the load on the caravan axle, but train weight is unchanged. As long as you stick within the cars legal towing limit, gross vehicle weight, axle loads, and train weight why not just take 60+ kg out of the caravan and into the car.
Does not matter how much weight you transfer to the vehicle, the police check the plates for maximum weights. If the caravan is post Oct 2012 it will have a fixed plate on the chassis. However the insurance company may not agree with transferring weight to car as the sum of the maximum weights for both units will exceed the maximum gross train weight.
 
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The noseweight CANNOT be part of the towed load, it has to be counted within the car's maximum weight and CANNOT be counted twice.

The OP will need to ensure the Gross Train Weight isn't exceeded.
 
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Does not matter how much weight you transfer to the vehicle, the police check the plates for maximum weights. If the caravan is post Oct 2012 it will have a fixed plate on the chassis. However the insurance company may not agree with transferring weight to car as the sum of the maximum weights for both units will exceed the maximum gross train weight.
I did actually say that as long as specified weight were not exceeded. As far as towing trailer is concerned surely there are two areas. One is the need to recognise plated weight for licence considerations. So here even if the caravan were unloaded the driver could be illegal. But the other is towing a loaded trailer but not one that exceeds the MTPLM. Following your logic the driver could be at fault if towing the unladen caravan. But if the licence allowed it and the driver did not exceed the specified weight surely he is not illegal? As one or the rare souls who has been stopped and escorted to a DVSA weighbridge it is not the Police that weigh the outfit.
 
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I did actually say that as long as specified weight were not exceeded. As far as towing trailer is concerned surely there are two areas. One is the need to recognise plated weight for licence considerations. So here even if the caravan were unloaded the driver could be illegal. But the other is towing a loaded trailer but not one that exceeds the MTPLM. Following your logic the driver could be at fault if towing the unladen caravan. But if the licence allowed it and the driver did not exceed the specified weight surely he is not illegal? As one or the rare souls who has been stopped and escorted to a DVSA weighbridge it is not the Police that weigh the outfit.
The 3500kg outfit limit applied to B-only licence holders is based on gross plated weights of car and trailer/caravan added together - even if the actual weights are much lower, eg if both are unladen. If a licence infringement is suspected, no weighing is necessary.

Weight limits applicable to the car and/or trailer/caravan are based on actual weights.
 
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I did actually say that as long as specified weight were not exceeded. As far as towing trailer is concerned surely there are two areas. One is the need to recognise plated weight for licence considerations. So here even if the caravan were unloaded the driver could be illegal. But the other is towing a loaded trailer but not one that exceeds the MTPLM. Following your logic the driver could be at fault if towing the unladen caravan. But if the licence allowed it and the driver did not exceed the specified weight surely he is not illegal? As one or the rare souls who has been stopped and escorted to a DVSA weighbridge it is not the Police that weigh the outfit.

There is no need to take you to a weigh station for the police to get a conviction as all they need to do is to check the plates on the towing vehilce and the trailer to see if the sum exceeds the gross maximum train weight of the towing vehicle. Does not matter if both units are totally empty.
 
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There is no need to take you to a weigh station for the police to get a conviction as all they need to do is to check the plates on the towing vehilce and the trailer to see if the sum exceeds the gross maximum train weight of the towing vehicle. Does not matter if both units are totally empty.

That only applies for driving licence purposes but if you have a B+E licence it's the actual weights which are important. The sum of the towing vehicle'plated weight and the MTPLM of the trailer can well exceed the plated gross train weight so long as the sum of the actual weights don't.
 
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This one has been debated a number of times before. You are correct in that noseweight transfers to the car which reduces the load on the caravan axle, but train weight is unchanged. As long as you stick within the cars legal towing limit, gross vehicle weight, axle loads, and train weight why not just take 60+ kg out of the caravan and into the car.

The axle load doesn't change when the caravan is hitched up to the car. The load on the jockey wheel just transfers to the car. The total weight of the caravan standing on its own is the axle load plus the load on the jockey wheel. The car is towing the axle load and carrying, not towing, the noseweight.
 
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That only applies for driving licence purposes but if you have a B+E licence it's the actual weights which are important. The sum of the towing vehicle'plated weight and the MTPLM of the trailer can well exceed the plated gross train weight so long as the sum of the actual weights don't.
Sorry have to disagree with you as the issue is the maximum gross train weight fo the vehicle that is in question. Not sure why you have decided to bring 3500kg etc into the conversation? Are you saying if the combination is below 3500kg the gross maximum train weight of the vehicle can be exceeded?
 
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The axle load doesn't change when the caravan is hitched up to the car. The load on the jockey wheel just transfers to the car. The total weight of the caravan standing on its own is the axle load plus the load on the jockey wheel. The car is towing the axle load and carrying, not towing, the noseweight.

TBH I am being a bit thick but your post does not make sense to me? As far as I am aware it is the maximum gross train weight of the vehicle that counts and nothing else. If stopped not even the DVSA or police have the authority to check your nose weight as that means the trailer needs to be detached from the towing vehicle and that is not going to happen.
 
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The 3500kg outfit limit applied to B-only licence holders is based on gross plated weights of car and trailer/caravan added together - even if the actual weights are much lower, eg if both are unladen. If a licence infringement is suspected, no weighing is necessary.

Weight limits applicable to the car and/or trailer/caravan are based on actual weights.

Yes it’s a bit like the French autoroute speed restrictions where it is plated weights not actual weights that govern your outfits actual maximum speed. But in my posts I did refer to licence conditions and assumed the OP knows what license is held.
 
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TBH I am being a bit think but your post does not make sense to me? As far as I am aware it is the maximum gross train weight of the vehicle that counts and nothing else. If stopped not even the DVSA or police have the authority to check your nose weight as that means the trailer needs to be detached from the towing vehicle and that is not going to happen.

My Caravan was detached from the car when checked at a Highways Agency weighbridge near Ringwood. In such circumstances noseweight could have been checked by having the van wheels on the weighbridge and jockey wheel on dry land. And shuffling around. But they were not interested in noseweight it was car axles, car weight, and caravan total. Plus tyres, lights etc.
 
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Sorry have to disagree with you as the issue is the maximum gross train weight fo the vehicle that is in question. Not sure why you have decided to bring 3500kg etc into the conversation? Are you saying if the combination is below 3500kg the gross maximum train weight of the vehicle can be exceeded?

No, if you read my reply correctly you will see that I am saying that the sum of the plated GVW of the car and the MTPLM of the trailer may exceed the plated gross train weight so long as the sum of the actual weights doesn't.

A car with a GVW of 2000kg and a plated gross train weight of 4000kg can tow a trailer with an MTPLM of 2500kg so long as the actual gross train weight doesn't exceed 4000kg.

TBH I am being a bit think but your post does not make sense to me? As far as I am aware it is the maximum gross train weight of the vehicle that counts and nothing else. If stopped not even the DVSA or police have the authority to check your nose weight as that means the trailer needs to be detached from the towing vehicle and that is not going to happen.

Without detaching the trailer from the towing vehicle there is no way of checking whether its MTPLM is exceeded or not.

Not only the maximum gross train weight must not be exceeded, but also the GVW of the towing vehicle and all axle loads, including that of the trailer.
 
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Unfortunately there are so many incorrect interpretations of how the authorities will assess an out for or its driver, that so much confusion reigns.

There are two main branches that need to be satisfied.

1. The drivers entitlement:-
The simple one becasue it purely based on the registered (Paper) Maximum Authorised Masses of the vehicles involved is the drivers entitlement. If the combined MAM's do not axceed 3500kg then the driver only needs Cat B. If the combined MAM's exceed 3500 even just by 1kg then teh driver must have the Cat Be, This is purely a paper calculation and is black and white.

2. The mechanical and legal limits for the tow vehicle and trailer.
Here the overriding LIMITS are the Gross Vehicle Weight of the solo tow vehicle and the Gross Train Weight of the coupled outfit. and the respective maximum axle loads as defined on the tow vehicles weights plate. The important aspect of all of these is they are mechanical limits and NOT paper assumptions about maximum authorise weights. The authorities cannot prosecute for exceeding any of them without a verified measurement on a authorised measuring system.

Provided the coupled tow vehicle (i.e. where the trailer's actual nose is applied to, and thus forms part of the cars total load) has not exceeded any of its axle limits or the Gross Vehicle Weight limit, it can lawfully tow a trailer with a measured axle load up to but not exceeding the difference between the GTW-GVW. This does not define the trailers MTLPM or MAM, so it is perfectly legal to tow a part loaded trailer up to the GTW-GVW value even if its stated MTPLM is greater.
 
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...Our caravan has a MIRO of 1085kg. It has an MLTPM of 1260kg. The car has a braked towing capacity of 1200kg and a kerbweight of 1565kg. On the face of it, I thought the car would not legally be allowed to tow the van due to the MLTPM, however my understanding is that when the van is attached to the car the nose weight is transferred to the car, therefore the towing weight is less, and therefore could be under the 1200kg.

I have a public weighbridge round the corner from me so am going to take the van there for some measurements attached/detached from the car.

Am I right in my logic/thinking that if the van is under 1200kg when attached to the car then it is perfectly acceptable (and legal) to tow with our BMW, despite it potentially weighing more than that when it is not attached to the car?

Thanks in advance for all your help.

Hello Thematrix12

I am confident your perception is correct. The 1200kg braked towing capacity on relates to the load carried by the trailer road wheels, so as you have suggested the actual nose load the trailer produces is carried by the car and must be accounted for in the cars loading.

With a trailer of 1200kg the EU construction regs are based on a minimum nose load of 4% = 48kg, but caravanners normally try to run with a 5 to 7% nose load which would be would expect a range of 60 to 84kg. Do check with the towbars "S" value which is the limit for that particular design.

Whilst I'm not suggesting you should try to take advantage of this but most weighbridges will have an uncertainty of between +/-10 to +/-20kg.

Using the convention towing ratio calculation (Caravan MTPLM/ Cars Kerbweight)x100%
your outfit wold be 1260/1565 = 80% and thus well within any industry advisories.
 
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Thanks all for your super quick replies. I won't lie.. A lot of the discussion has gone over my head! I'm going to have a dig around to find the other weights for the car and report back but it sounds like I'm being sensible (for once!) and perfectly correct from a legal perspective. 👍🏼
 
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Hello Thematrix12

I am confident your perception is correct. The 1200kg braked towing capacity on relates to the load carried by the trailer road wheels, so as you have suggested the actual nose load the trailer produces is carried by the car and must be accounted for in the cars loading.

With a trailer of 1200kg the EU construction regs are based on a minimum nose load of 4% = 48kg, but caravanners normally try to run with a 5 to 7% nose load which would be would expect a range of 60 to 84kg. Do check with the towbars "S" value which is the limit for that particular design.

Whilst I'm not suggesting you should try to take advantage of this but most weighbridges will have an uncertainty of between +/-10 to +/-20kg.

Using the convention towing ratio calculation (Caravan MTPLM/ Cars Kerbweight)x100%
your outfit wold be 1260/1565 = 80% and thus well within any industry advisories.

Thanks John. We haven't actually put the tow bar on the BMW yet as wanted to make sure it was legally feasible to tow the van before shelling out to do so. I believe the tow bars we are looking at have a nose weight value of 75kg.👍🏼
 
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It’s the car makers specification fir nose weight that is the governing limit. Knowing this you then have a towbar that is designed for the car. The Owners Manual should state the towbar noseweight limit.
 
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It’s the car makers specification fir nose weight that is the governing limit. Knowing this you then have a towbar that is designed for the car. The Owners Manual should state the towbar noseweight limit.
Hello Clive,
This is not quite true.

I have seen it but I can't remember where, where the car manufacturer had a 90kg nose load limit in their specifications, but the towbar it's self had an 80kg limit. Perhaps the car had a generic towbar for a model range, and the fitters attached the wrong data plate to the towbar? I don't know.

However as with all load limits, you have to abide by the lowest when there is a conflict of values.
 
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Hello Clive,
This is not quite true.

I have seen it but I can't remember where, where the car manufacturer had a 90kg nose load limit in their specifications, but the towbar it's self had an 80kg limit. Perhaps the car had a generic towbar for a model range, and the fitters attached the wrong data plate to the towbar? I don't know.

However as with all load limits, you have to abide by the lowest when there is a conflict of values.

Just like the weight plate on car and caravan, the towbar must be supplied with the plate attached by the manufacturer.

Maybe in the above case, the manufacturer fits a towbar from a different source to what is offered in the aftermarket.
 
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Hello again, Thematrix12,

In the light of the pictures you have sent, the data plate as Roger L has pointed out gives you a GTW-GVW of 1275kg, which comfortably encompasses your caravans MTPLM without having to account for load transfers. 😎

Just for your information the VIN plate gives you from top to bottom
Gross Vehicle Weight
Gross Train Weight
Front axle limit , Rear axle limit

Every EU sold vehicle has the data in the same format.
 

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