Wanted van rated towing of 3.5t,

Markd

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I've been investigating my GVW, GTW, etc on the Motorhome in the last few days actually as a precursor to getting a weight uprate ...

Post Motorhome conversion, Autotrail state the GVW and the GTW - but they do also state a max towing weight as well - which is GTW minus GVW. So that does
mean like Nabsim says, you can't take spare capacity from the van and put a greater load in the trailer.
As far as Panel vans go, my VW LT was just the same - the VIN had a GVW of 4600 and a GTW of 6600, and the handbook stated a maximum towed weight of 2000. So no weight loss in the van to allow a heavier trailer allowed there either.
The info is not on the VIN plate, but very likely in the drivers handbook and I bet your Sprinter will have exactly the same stipulations as my VW and Nabs Mercedes.
The phrase ".....any spare weight capacity can be used by the trailer, so long as the GCW and trailer GVW are not exceeded" could be key, but what it the manufacturer has implicitly stated a towing limit? Their design limit will superceed that phrase I am sure.
Note the wording earlier in that sentence also ... "To help find ...". So guidence only.


PS. I was not familiar with the term "GCW" so I did a search .... something the unwary need to watch out for - the term GTW has two different (VERY different) meanings when it comes to towing and weight limits. In the UK, GTW = Gross Train Weight, yes? In some other countries, the term GTW changes to GCW - Gross Combination Weight and GTW changes meaning to Gross Trailer Weight!
e.g. On-line info such as:
"Gross Trailer Weight (GTW) is the same as Gross Vehicle Weight (GVW) when referring to a trailer. Again, the only way to accurately determine the GCW is to drive the entire assembly on a scale."
or
"Gross Combination Weight (GCW) – Equals GVW plus GTW."

something for the unwary to become aware of if searching the web for info on trailers and weight limits.



Little extra bit ...
Picked this paragraph up from the What Car website:
"The popular Mercedes Sprinter only has a towing capacity of two tonnes, but as with most Sprinter vans there is an option for everything, and a special reinforced trailer coupling can be specified to transform the maximum into 3500kg, which makes it far more versatile"
So Mercedes are saying to tow over 2000kg and upto an extra 1500kg, you need a special reinforced trailer coupling. If the GTW limit was as simple as the trailer can be any weight as long as the GTW is not exceeded, the driver could have an empty Sprinter and likely tow 3000kg. So why the need for the reinforced coupling?
It would be pretty lethal to have an empty van and a 3T trailer!
Isn't there a legal max ratio for trailer to tow vehicle weight?
 

Markd

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Apparently manufacturers do not homologate some vehicles for towing.
This will be shown either 0000 or a blank line on the vin plate for max train weight.
It would be illegal to tow with these vehicles.
 

Fazerloz

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I've been investigating my GVW, GTW, etc on the Motorhome in the last few days actually as a precursor to getting a weight uprate ...

Post Motorhome conversion, Autotrail state the GVW and the GTW - but they do also state a max towing weight as well - which is GTW minus GVW. So that does
mean like Nabsim says, you can't take spare capacity from the van and put a greater load in the trailer.
As far as Panel vans go, my VW LT was just the same - the VIN had a GVW of 4600 and a GTW of 6600, and the handbook stated a maximum towed weight of 2000. So no weight loss in the van to allow a heavier trailer allowed there either.
The info is not on the VIN plate, but very likely in the drivers handbook and I bet your Sprinter will have exactly the same stipulations as my VW and Nabs Mercedes.
The phrase ".....any spare weight capacity can be used by the trailer, so long as the GCW and trailer GVW are not exceeded" could be key, but what it the manufacturer has implicitly stated a towing limit? Their design limit will superceed that phrase I am sure.
Note the wording earlier in that sentence also ... "To help find ...". So guidence only.


PS. I was not familiar with the term "GCW" so I did a search .... something the unwary need to watch out for - the term GTW has two different (VERY different) meanings when it comes to towing and weight limits. In the UK, GTW = Gross Train Weight, yes? In some other countries, the term GTW changes to GCW - Gross Combination Weight and GTW changes meaning to Gross Trailer Weight!
e.g. On-line info such as:
"Gross Trailer Weight (GTW) is the same as Gross Vehicle Weight (GVW) when referring to a trailer. Again, the only way to accurately determine the GCW is to drive the entire assembly on a scale."
or
"Gross Combination Weight (GCW) – Equals GVW plus GTW."

something for the unwary to become aware of if searching the web for info on trailers and weight limits.



Little extra bit ...
Picked this paragraph up from the What Car website:
"The popular Mercedes Sprinter only has a towing capacity of two tonnes, but as with most Sprinter vans there is an option for everything, and a special reinforced trailer coupling can be specified to transform the maximum into 3500kg, which makes it far more versatile"
So Mercedes are saying to tow over 2000kg and upto an extra 1500kg, you need a special reinforced trailer coupling. If the GTW limit was as simple as the trailer can be any weight as long as the GTW is not exceeded, the driver could have an empty Sprinter and likely tow 3000kg. So why the need for the reinforced coupling?
It could be as with Fiat/ Dodge vans you can get a heavier duty chassis and heavy duty tow packages with compensator plates to enable heavier ball and tow weights. Not generally known about in this country.
 

RV2MAX

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All iveco dailys can pull a 3.5 tonne trailer , even at gvm , and handle it well from my experience . They are also rear wheel drive which is a big plus for towing , especially when heavy . Dont forget to factor in towball loading when loading prime mover to gvm .
 

Markd

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VW and others uprate towing capacity for same van when RWD.
Yes with a long overhang from tow ball to rear axle the increase in load can be significant.
 

wildebus

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VW and others uprate towing capacity for same van when RWD.
Yes with a long overhang from tow ball to rear axle the increase in load can be significant.
Your last point raises an interesting question. As I mentioned earlier, I am in the middle of a discussion on GVW, GTW, max towing weight, etc on my own van, which is why a lot of this is fresh in my head as looking into it....
I have a 6.7M Coachbuilt with 1250kg max towing weight (and the GTW is 1250 greater than the GVW). There are two sister models with identical weight limits (including front and rear axles) and wheelbases. One of those is 6.7M long also, but the other is 7.4M long, and that extra length has got to be more overhang if the same wheelbase? So an extra 700mm distance from Axle to Tow Ball but no difference in rear axle weight and towing numbers.
Seems a bit odd and I can only imagine that they went for the lowest common demoninator for the weights to list them all the same for simplicity?
 

Nabsim

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Do the tow bars come out on a swan neck Dave? It may be possible they are mounted the same if same wheelbase but longer swan neck on longer wheelbase. Think that’s just about understandable lol
 

Markd

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As far as the tow vehicle is concerned the additional overhang doesn't affect the safe axle load nor the max train weight.
Mind you I expect the longer van weighs more to start with a d has more of that weight on the back axle.
Driveability may be affected by the additional lever arm I suppose.
However for any given trailer nose weight there will be a increase in load imposed on rear axle and decrease on front axle.
I know you like doing sums so it's time to crack out the calculator and check the changes.
I seem to recall that you've got a fair bit of capacity available on your rear axle?
As you have the shorter option it shouldn't be too big an issue.
 

Markd

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Do the tow bars come out on a swan neck Dave? It may be possible they are mounted the same if same wheelbase but longer swan neck on longer wheelbase. Think that’s just about understandable lol
That would be a long swan neck!
The chassis must surely extend an extra 700mm as well?
 

wildebus

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I just got an email back from AutoTrail regarding towing weights (and confirming what I hoped for my own MH) and there is an interesting bit of info in there which may be worth sharing as other motorhome manufacturers are likely to be similar as they all in reality use the same chassis range ...

I was sent a list in Excel of a whole bunch of Motorhome models from 2008 and their towing weights, and at the bottom of this list is this note:

NOTE
The towable weights are the maxixmum permitted total weight of the trailer and its contents combined.
All weights are based on a static tow-ball loading of 75 kg (tow bar manufacturers may specify a lower weight).
Any loaded trailer weighing over 750 kg must be braked.
* If the maximum authorised vehicle vehicle weight is not fully utilised, then the towable weight can be increased accordingly.

And the * note at the bottom is the interesting bit. Saying essentially that spare weight can be shifted to the trailer. But only for those models noted with a * though.
Chassis TypeMaximum Towable Weight
FIAT1040 kg
FIAT1050kg
FIAT1120 kg
FIAT1250 kg
FIAT1340 kg
MERCEDES 3151200 kg
MERCEDES 3181200 kg
FIAT / ALKO1000 kg*
FIAT / ALKO1250 kg*

There are four chassis types listed in total - two Fiat and two Mercedes. The weights for the "all Fiat" ones vary a fair bit depending on the models, but the Mercedes are the same for both models and the Alko one has two values depending on the Motorhome model.

And it is only the Alko which allows spare Payload to be transferred to the Trailer. The rest are fixed.
 
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Markd

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Great info from Autotrail - thanks.
I have an old Bessacarr on Fiat-Alko chassis.
The Alko chassis continues 'full section' to the 'back' of coach build. So I can see how that would allow extra weight in trailer.
As it happens I've taken the tow bar off - it was extra length to 'cover' the folded bike rack and weighed 60 kg!!
 
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