Towing a caravan . Cooling issues ?

[ALFAitalia]

We're going round in circles. Before 16 December 2021 that could have been illegal (depending on the driver). Now it's not.

Towing with a car

Towing trailers, caravans and horseboxes with a car, including the weight and size limits, and what licence you need to have

www.gov.uk

You are getting max towing weights confused with the (now defunct) licence restrictions ........The maximum towing weight laws were around years before that licence restrictions came in. Those restrictive laws effectively meant that those customers could not tow anything but the tinniest vans as the 3.5 limit limit was gross weight.....so the gross laden weight of the car added to the gross weight of the caravan. So even a 1600kg Mondeo has a gross of around 2.5 ton......leaving only about 1000 for the caravan.....a tiny two berth or a trailer tent! Was a major issue for us caravan dealers.....many younger drivers knowing nothing about it until I told them.....glad that nonsense is gone!!!

 

[GrahamT]

But nobody is saying that are they?

Really? Could you let me know which cars these are?

E220d Estate, Kerb weight 1780 kg. Max. towing limit 2100kg.

Mercedes-Benz E-Class Estate - Practical Caravan

It is impressive with or without a caravan on tow, and has class-leading luggage space, but can the Mercedes-Benz E-Class justify its price? Let's find out

www.practicalcaravan.com

 

[Bobby Dazzler]

It would be interesting to see such a vehicle that has a legally permitted towing weight greater than its GVW.

I can see one from where I am:
Gross vehicle weight 3050kg
Gross train weight 6200kg
Max recommended towing weight 3150kg

 

[JHS]

I can see one from where I am:
Gross vehicle weight 3050kg
Gross train weight 6200kg
Max recommended towing weight 3150kg

Tell more? But 3050:3250 is probably regarded as 1:1

 

[JHS]

E220d Estate, Kerb weight 1780 kg. Max. towing limit 2100kg.

Mercedes-Benz E-Class Estate - Practical Caravan

It is impressive with or without a caravan on tow, and has class-leading luggage space, but can the Mercedes-Benz E-Class justify its price? Let's find out

www.practicalcaravan.com

Interesting, physically capable of towing a 2100 trailer BUT, that would be illegal as the trailer would weigh more than the tow car.
Don't take my word for it, you just have to convince the roadside inspector.

 

[JHS]

Mercedes G Wagen can tow 3500kg

But not legally.

 

[BTB 500]

You are getting max towing weights confused with the (now defunct) licence restrictions ........The maximum towing weight laws were around years before that licence restrictions came in. Those restrictive laws effectively meant that those customers could not tow anything but the tinniest vans as the 3.5 limit limit was gross weight.....so the gross laden weight of the car added to the gross weight of the caravan. So even a 1600kg Mondeo has a gross of around 2.5 ton......leaving only about 1000 for the caravan.....a tiny two berth or a trailer tent! Was a major issue for us caravan dealers.....many younger drivers knowing nothing about it until I told them.....glad that nonsense is gone!!!

I'm not confused ... the licence-based restrictions started in 1997! Most of my friends (fellow dog agility competitors) drive vans which of course have a high MAM - that did make it hard for the younger ones to find caravans whose MTPLM wouldn't put the combination over 3500 kg in total. The solution was to take the separate "B+E" towing test though, which many did.

 

[BTB 500]

Interesting, physically capable of towing a 2100 trailer BUT, that would be illegal as the trailer would weigh more than the tow car.
Don't take my word for it, you just have to convince the roadside inspector.

It's not illegal for a trailer to weigh more than the tow car. That restriction only applied to certain drivers (test passed from 1 January 1997 to 18 January 2013), and was dropped on December 16th 2021. The limit of 3500 kg GTW was also dropped on the same date (and didn't apply to those who had passed their test before 1997 anyway).

But not legally.

Why? If a car is plated to tow 3500 kg then it's legal for any driver to tow up to that weight with it now, subject to staying within the vehicle's GTW (since December 16th 2021).

I've posted UK Government links showing the current law. Please provide supporting evidence if you think those are wrong.

 

[JHS]

It's not illegal for a trailer to weigh more than the tow car. That restriction only applied to certain drivers (test passed from 1 January 1997 to 18 January 2013), and was dropped on December 16th 2021. The limit of 3500 kg GTW was also dropped on the same date (and didn't apply to those who had passed their test before 1997 anyway).



Why? If a car is plated to tow 3500 kg then it's legal for any driver to tow up to that weight with it now, subject to staying within the vehicle's GTW (since December 16th 2021).

I've posted UK Government links showing the current law. Please provide supporting evidence if you think those are wrong.

So you now accept that it is the GTW that is the deciding factor?

 

[BTB 500]

So you now accept that it is the GTW that is the deciding factor?

No, because any car that can tow 3500 kg must have a GTW that is higher than that. And there are no licence restrictions on maximum GTW any more - only on trailer MAM (for those who passed their test from 1997 onwards).

 

[JHS]

No, because any car that can tow 3500 kg must have a GTW that is higher than that. And there are no licence restrictions on maximum GTW any more - only on trailer MAM (for those who passed their test from 1997 onwards).

BUT you posted this:
Why? If a car is plated to tow 3500 kg then it's legal for any driver to tow up to that weight with it now, subject to staying within the vehicle's GTW (since December 16th 2021).

I will retire from this circular discussion and just keep within my GTW and MB towing limits, safe in the knowledge that I wont be prosecuted.

 

[BTB 500]

BUT you posted this:
Why? If a car is plated to tow 3500 kg then it's legal for any driver to tow up to that weight with it now, subject to staying within the vehicle's GTW (since December 16th 2021).

I will retire from this circular discussion and just keep within my GTW and MB towing limits, safe in the knowledge that I wont be prosecuted.

Of course you must always stay within the car's plated GTW (and corresponding braked trailer limit), and noseweight limit. My point is simply that previous restrictions (for some drivers) of a maximum GTW of 3500 kg, trailer not being heavier than the car, etc. no longer apply. So anyone can now quite legally tow up to 3500 kg with a G Wagen (which I believe has a GTW of 6700 kg).

 

[Bobby Dazzler]

Tell more? But 3050:3250 is probably regarded as 1:1

It’s a Mercedes ML.

 

[GrahamT]

Interesting, physically capable of towing a 2100 trailer BUT, that would be illegal as the trailer would weigh more than the tow car.
Don't take my word for it, you just have to convince the roadside inspector.

Oh dear.

 

[Merc220cls]

In answer to the OP I tow a Coachman 520/4 with my CLS shooting brake and notice no overheat problems whatsoever.
Manufacturers will cover their backs by saying “you must have” and of course they will cream off more revenue from the customer.
One thing I like, well two actually on my CLS it has a water temperature gauge and if you go into the engine performance screen it shows engine oil temperature which I tend to view when pulling on long uphills. My previous car, a Jaguar XF had none of these, only a warning light when lit of course would Probably have been too late. Thankfully it that never happened.
I also agree with caravan forums attitude being “anal”. I’ve posted on a few of them and suffered the wrath of correctness.
Forums should try and remain helpful to posts but that’s human nature I suppose.

 

[BfgSLKMan]

The upgrade involves swapping the 450w fan for a 600w one. I have towed at 2000kg up the A76 from south of France (10% in some parts) at 1000m, no issues with the temp guage moving, just the gearbox oil getting a bit warmer with the factory fitted towbar. If you only ever tow in the UK and with a generally lighter U.K. caravan (than German ones!) then i can’t see a need for a new fan?

 

[Delboy0127]

I have just had fitted a tow bar with dedicated electrics to my used W213 estate diesel. The MB dealers suggested that the cost for them to do it would frighten me. (it did !) so I went to a tow bar specialist on their suggestion .
I did question my local dealers and was told that the factory fitted upgrades are to permit towing the Maximum weight up an Alp in 40c temperatures. I have no plans to do that !

On a caravanning club forum I recommendet the company I used and then got dire warnings about my failure to have the 'proper MB cooling upgrades for the engine and gearbox'.

My question is about other's experiences about going down the road I have. Is there any record of problems resulting from towing well under the 2200 KG limit which MB list for this model ? (My caravan has a mtpw of 1300 kg.

Following unrepairable failure of a Factory fit Oris Deployable Towbar. A detachable replacement was fitted.
This also included a new 13 pin socket. Following fitment of the new Towbar a dashboard warning light came on , Which now constitutes a MOT failure as advised by Mercedes by email.
The car has been on the Star machine and Mercedes advice the only way to remove the warning is to switch off the Towbar electrics which then disconnects the wiring to the new socket.
It appears the company that fit the Tow bar used the existing wiring from the old socket and wired the new socket with this wiring, as I understand nothing else was changed
The question is was this correct way to wire the new socket ? or should a dedicated wiring kit have been used.
Has any else has a similar problem? Any assistance appreciated.

 

[jasonh]

Initially I'd think the replacement towbar company did exactly the right thing. The physical/mechanical part of the towbar failed (and was replaced). The 13 pin electrics should remain unchanged. Just replacing the 13 pin socket using the original wiring should be fine.

However, based on what you're seeing I suspect the error is coming from a sensor that detects that the deployable towbar is not detected as fully deployed and locked.

MB will want you to fit a deployable replacement because that's all they know.

A full replacement by a towbar place would probably involve deactivating the MB towbar in XENTRY and fitting an aftermarket dedicated wiring loom (that is intelligent and doesn't require coding).

If it were me I'd be looking at two options:

1) Use XENTRY or other diagnostics to remove the deployable toward feature and instead add a fixed towbar feature. I don't know for certain this is possible but if a fixed towbar is a MB option then it should be entirely possible.

2) Link or bypass the "deployed" sensor so when the car checks it shows the towbar as deployed. Again I don't know 100% that this is possible but I suspect it is.

 

[Delboy0127]

Initially I'd think the replacement towbar company did exactly the right thing. The physical/mechanical part of the towbar failed (and was replaced). The 13 pin electrics should remain unchanged. Just replacing the 13 pin socket using the original wiring should be fine.

However, based on what you're seeing I suspect the error is coming from a sensor that detects that the deployable towbar is not detected as fully deployed and locked.

MB will want you to fit a deployable replacement because that's all they know.

A full replacement by a towbar place would probably involve deactivating the MB towbar in XENTRY and fitting an aftermarket dedicated wiring loom (that is intelligent and doesn't require coding).

If it were me I'd be looking at two options:

1) Use XENTRY or other diagnostics to remove the deployable toward feature and instead add a fixed towbar feature. I don't know for certain this is possible but if a fixed towbar is a MB option then it should be entirely possible.

2) Link or bypass the "deployed" sensor so when the car checks it shows the towbar as deployed. Again I don't know 100% that this is possible but I suspect it is.

Jason thank you so much for-your very detailed reply All of what you have said I agree with 13 pin wiring is 13 pin wiring and should be ok which it is, all of the functions of the socket are working 100% The star machine can be told no tow bar is fitted which then shuts of the 13 pin socket off. So hopefully the star system can be told a none deployable tow bar is being fitted, following fitment of a dedicated wiring loom . Sincere thanks for your input
Has any else had a Detachable towbar and electrics fitted to a E class estate S213 2017, without any wiring problems.

 

[jasonh]

You might get away with just using XENTRY (Star) to change the towbar type (without having to change the module/wiring). I'd suggest using a MB specialist, not MB because I suspect they'll refuse!