Outfit Advice

[StevenHall]

I was looking to buy a van royce caravan but the deal has fell through due to the caravan not being as described.

What i what to know is ,is my car suitable to tow a lunar delta 610/4 which was made in 1996..here are the specs:

My car..2005 55 plate BMW E90 330i petrol auto saloon..

kerbweight of car..1540kg.

permitted gross weight..1985kg

V5 states that braked towed trailers/loads..1700kg

Caravan details..1996 lunar delta 610/4 twin axle 20ft body.

unladen weight..just over 1100kg @(22.2cwt)

the plate on the door has a MAW weight of 1445kg.

The question is that the van is quite a big one in length,but seem very light in comparision with other slightly smaller caravans who are made by other manufactuers but those towing figures seem to stack up OK or am i missing something somewhere..or are lunar caravans just generally lighter..i take it the maw weight is the total weight of the caravan with all the personal extras needed for a trip away..ie: the gross caravan weight.

Somebody please help me as i have been through loads of different websites but they dont seem to go back that far so i can check to see if those weights for that particular van are correct.

Best Regards

Steve.

 

[RayS]

Hi Steve, sorry to say i don't think this is a very good match. The "rule of thumb" (not law, not cast in concrete) is that the MAW (as it used to be called) of the van should not be greater than 85% of the declared kerb weight of the car.

This would give you a maximum MAW or MTPML as it is now called of around 1300Kg for the van, and your proposed van is way over this.

Experienced towers sometimes get around 90% or possibly even more, taking care not to exceed the maximum towing limit of the car, but this is not recommended.

The car being petrol rather than diesel won't help either, as the maximum torque is usually developed at much higher rpm and size for size may be lower than the equivalent diesel anyway.

You will probably get more advice from others along the saem lines but we have to give advice as requested and I'm afraid it is either smaller van or change the car.

 

[StevenHall]

I am an experianced tower as i am a hgv artic/drawbar driver so i could probably tow over the 85% ruling ok but i dont want to buy this van if it is going to be far to heavy.

 

[Robtel]

Hi Steve,

What RayS has posted is correct.

The only thing I would add is, how sure are you that your car kerbweight is the figure you have quoted? The reason I ask is that a lot of car manufactures are guilty of giving a "from xyz kg" in their handbook. This can vary quite a bit depending on what model of that car you have. For example my hanbook says from 1840 kg but actual kerbweight is almost 100kg above that. A visit to a local weighbridge will only cost a few pounds and might be of great assistance.

Re Lunar caravans - they do/did have a reputation for making light weight caravans. I used to have a Lunar Lexon which was markedly lighter than other vans of a similar length manufactured by others.

 

[StevenHall]

When i saw the van i thought it looked a big van to pull with my car but the dealer told me that it would be ok and when we looked into the details/weights etc it looked like it would be OK but i just want some reassurance from people on here.

I am only going off what the cars handbook states is the kerbweight,i haven't had the car weighed at a weighbridge.

 

[Lutz]

The kerbweight that you quote (1540kg) sounds very realistic for a BMW 330i. Published figures always tend to be lower than actual ones (I have yet to come across an example where this is not the case), so if you use the kerbweight stated in your handbook you will be on the safe side.

 

[StevenHall]

Thanks Lutz

I have been back up to the dealers today just to clarify a few points:

1: Cars kerbweight = 1540kg

2: Caravans unladen weight = 1112kg

3: Allowable caravan payload = 284kg

4:Total caravan gross weight = 1396kg

In my eyes is a really lightweight twin axle caravan as it is constructed around a aluminium chassis.

I know the above figures are true as the dealer had a brochure for the lunar delta range dating back to 1996,so i know the car/caravan match isn't an 85% match,more like 90% match but i think it all will be ok..like everybody on here knows the 85% rule is only a guideline and isn't set in stone.

Could i load the car with the heavier items,taking care not to overload it of course to effectively raise the cars kerbweight and put the lighter items over the caravans axles with nothing in the front lockers to keep the caravans weight as light as possible.

 

[Lutz]

The calculated weight ratio is always a worst case scenario, comparing the car in its lightest possible condition with a fully laden caravan. In practice, this is hardly ever going to occur in reality. As you correctly infer, the actual weight ratio will always be more favourable once you've got stuff aboard the car and if the caravan is not fully laden.

 

[colin-yorkshire]

hi steven

I don't want to douse anybodys fire but reading the tread it seems to me that while the info you have been given seems to be good it is not complete.

as caravaners we are restricted by weight constraints at every turn or that how it must seem, the golden rule in order to be completely legal is go by the lowest not the highest margin in any particular area as this has a knock on effect in calculating the legal limits and futhermore even if the legal limits are not reached the outfit could be impractical in use.

my advice is tread very carfully or you could find yourself falling in to a very expensive hole, been there done that on paper fine in practice completly the opposite.

taking things on face value can be misleading if you don't do a bit of research before hand.

take the figures you have been given :-

kerbweight of car..1540kg.

permitted gross weight..1985kg

V5 states that braked towed trailers/loads..1700kg

Caravan details..1996 lunar delta 610/4 twin axle 20ft body.

: Caravans unladen weight = 1112kg

: Allowable caravan payload = 284kg

:Total caravan gross weight = 1396kg

all the above figures seem quite reasonable but I don't see one for gross vehicle train weight, furthermore if the weight is removed from the trailer to get the weight down and added to the car where does it go probably in the boot this added to the nose weight of the van could btm out the suspension over bumps. overall towing stability could also be affected if the loading is not done precisely.

my advice would be go over the figures a few times calculating the what added to what is and if any of the figures are marginal don't do it and think again.

colin

 

[Lutz]

When you transfer payload from the caravan to the car, you do not affect the gross train weight in any way. As long as you stay within the gross vehicle weight limit specified for the car the suspension is unlikely to bottom out either except under severe conditions, so there is nothing wrong with sensible redistribution of payload from caravan to car, within the limits set.

 

[colin-yorkshire]

quote form lutz "When you transfer payload from the caravan to the car, you do not affect the gross train weight in any way."

This is true but I never said it did lutz. what I said was the figures given by steven DID NOT include the gross vehicle train weight, accually this is probably the most important figure of all as it is the total weight the car/van combo can weigh.

The more weight is added to the car up to it's gross vehicle weight the less trailer weight it will pull legaly, a problem I had with the mondeo the gross vehicle weight added to the maximum trailer weight "MTPLM" was +300kg more than the GVTW so to be legal one or the other had to shed +300kg, that was more than the user payload of the van ie 70kg less than the vans MIRO.

also "As long as you stay within the gross vehicle weight limit specified for the car the suspension is unlikely to bottom out either except under severe conditions," .sorry this is not true because with a vehicle loaded to its max GWV does not take into account the 75kg of nose weight on top. you know as well as I do that for calculation purposes the nose weight can be deducted from the MTPLM of the van, it does not dissapear as if my magic so it must be deducted from the vehicles GVW.

a car loaded up to the max that then has the nose weight added to it most definitly WILL btm out, unless of course you intend to tow with a hummer or something then its not a caravan you want to tow just add a few wheels to the bungalow and tow that.

colin

 

[Lutz]

Firstly, in the vast majority of cases, the maximum gross train weight is the sum of the max. gross vehicle weight and the towload limit. There are exceptions, notably Renault.

Secondly, the noseweight is not in addition to the GVW, but is included as part of the GVW. Therefore, a fully laden car towing a caravan will not have any more weight on the rear axle than a fully laden car solo. GVW is GVW, whether towing or not.

 

[colin-yorkshire]

hi

well here we go "Firstly, in the vast majority of cases, the maximum gross train weight is the sum of the max. gross vehicle weight and the towload limit. There are exceptions, notably Renault. I have no idea what criteria that statment comes from all I can say is the last 3 cars I have towed with the total GVTW was less than the GVW and MTPLM added together these were rover45, mondeo,and yes the renault.

"Secondly, the noseweight is not in addition to the GVW, but is included as part of the GVW. Therefore, a fully laden car towing a caravan will not have any more weight on the rear axle than a fully laden car solo. GVW is GVW, whether towing or not." I agree but that was not the impression given in previous posts nose weight was never mentioned untill I brought it up.

the suggestion as I saw it was, that it is ok to transfer exess weight from the van to the car to get a better weight ratio between car and van and loading the car up to it's GVW: BEFORE hanging the now reduced weighted van on.

 

[colin-yorkshire]

hi

well here we go "Firstly, in the vast majority of cases, the maximum gross train weight is the sum of the max. gross vehicle weight and the towload limit. There are exceptions, notably Renault. I have no idea what criteria that statment comes from all I can say is the last 3 cars I have towed with the total GVTW was less than the GVW and MTPLM added together these were rover45, mondeo,and yes the renault.

"Secondly, the noseweight is not in addition to the GVW, but is included as part of the GVW. Therefore, a fully laden car towing a caravan will not have any more weight on the rear axle than a fully laden car solo. GVW is GVW, whether towing or not." I agree but that was not the impression given in previous posts nose weight was never mentioned untill I brought it up.

the suggestion as I saw it was, that it is ok to transfer exess weight from the van to the car to get a better weight ratio between car and van and loading the car up to it's GVW: BEFORE hanging the now reduced weighted van on.

EDIT:- post should read "DIFFERENT" instead of "LESS"

 

[Lutz]

You say that the gross train weight of your last 3 cars was less than the sum of the GVW and the MTPLM of the caravan. That doesn't surprise me. I said that the gross train weight is normally the sum of the GVW and the towload, NOT the sum of GVW and MTPLM.

 

[ProfJohnL]

I think Colin has made an important point. Most people do not give a lot of thought to the GTW, becaue traditionally it has been the sum of the GVW allowable max traile weight. Notably Renault regularly produces figures where the GTW is less than the combined MAM's others are now beginning to come to light.

I know the data base I uses does not include GTW's and I don't know it the other common matching sites do so extra care about checking the results is becoming even more essential.

Colin, in your last post you said "a car loaded up to the max that then has the nose weight added to it most definitly WILL btm out, unless of course you intend to tow with a hummer or something then its not a caravan you want to tow just add a few wheels to the bungalow and tow that."

The criteria are the cars axle loads. If you fully load a solo vehicle, and then add the nose weight of a trailer you have over loaded it. As Lutz points out you must allow to the nose load within the cars loading which is determined by the permitted axle loading.

A car load to its max, should not bottom out unless it is being driven to fast for the given conditions.

This is an exact parallel to the point about GTW and MAM's.

Car manufacturers are being pushed to produce ever more 'green' vehicles, but naturally they don't wan't to make the cars seem any less effective than they used to be. Consequently I believe they are looking for ways to pare back the overall weight of a vehicle to improve efficiency, but still have a good published towing and load margins. They can do this by manipulating the figures to give apparently high individual load margins for boot, roof and trailer etc but preventing all these limits to be used collectively, by having a lower GTW.

 

[Lutz]

You say that the gross train weight of your last 3 cars was less than the sum of the GVW and the MTPLM of the caravan. That doesn't surprise me. I said that the gross train weight is normally the sum of the GVW and the towload, NOT the sum of GVW and MTPLM.

Just to clarify, the maximum permissible gross train weight is normally the sum of the maximum allowable gross vehicle weight and the towload limit specified by the car manufacturer. The towload is the axle load of the caravan/trailer, not its MTPLM.

 

[Lutz]

I think Colin has made an important point. Most people do not give a lot of thought to the GTW, becaue traditionally it has been the sum of the GVW allowable max traile weight. Notably Renault regularly produces figures where the GTW is less than the combined MAM's others are now beginning to come to light.

I know the data base I uses does not include GTW's and I don't know it the other common matching sites do so extra care about checking the results is becoming even more essential.

Colin, in your last post you said "a car loaded up to the max that then has the nose weight added to it most definitly WILL btm out, unless of course you intend to tow with a hummer or something then its not a caravan you want to tow just add a few wheels to the bungalow and tow that."

The criteria are the cars axle loads. If you fully load a solo vehicle, and then add the nose weight of a trailer you have over loaded it. As Lutz points out you must allow to the nose load within the cars loading which is determined by the permitted axle loading.

A car load to its max, should not bottom out unless it is being driven to fast for the given conditions.

This is an exact parallel to the point about GTW and MAM's.

Car manufacturers are being pushed to produce ever more 'green' vehicles, but naturally they don't wan't to make the cars seem any less effective than they used to be. Consequently I believe they are looking for ways to pare back the overall weight of a vehicle to improve efficiency, but still have a good published towing and load margins. They can do this by manipulating the figures to give apparently high individual load margins for boot, roof and trailer etc but preventing all these limits to be used collectively, by having a lower GTW.

GTW is invariably less than the combined MAM's. Usually GTW is the max. GVW plus the max. permissible towload.

 

[Lutz]

Vehicle emissions are determined in a solo condition and not when towing at gross train weight. Unless I'm mistaken, exhaust emissions are measured at GVW. Hence there is no incentive for car manufacturers to deliberately limit the gross train weight on the grounds of favourable emissions results. I strongly suspect that where the gross train weight is less than the sum of the GVW and the max. permissible towload then this has something to do either with engine cooling performance or that of the brakes, both of which are directly influenced by the total train weight.

 

[colin-yorkshire]

hi all,

john L "The criteria are the cars axle loads. If you fully load a solo vehicle, and then add the nose weight of a trailer you have over loaded it"

that is exactly the point I was trying to make, the assumption as I read it was that it was ok to remove weight from the van ie heavy objects like awnings ect in order to reduce the vans overhall mass and carry them in the car. without regard for the weight allready carried by the vehicle.

the maximum gross vehicle weight has a top figure for a fully loaded car "solo" that is unladen weight plus passengers and a resonable amount of luggage, unless the said vehicle is actually weighed on a weighbridge in this state it is impossible to know how much weight it is actually carrying before the trailer is hung on the back.

my point was that a car (not a hummer ect) may well be almost at it's limit once you have filled the tank,added the weight of the tow bar and filled the 5 seats put two dogs in the back hamper for the journey and filled the roof box with golf clubs fishing tackle ect, and then found room for the awning and poles (non european type) before hanging on its trailer and 75kg of nose weight. "get the picture" I did???.

ok, so if you dont have a roof box to fill, don't have any dogs to transport, no,passengers on the rear seats ect then maybe it is ok to put the awning on the rear seat and a bit of kit in the boot,

But was not inferred to by the posts.

I do not, (unlike some on this and other forums) have a background in engineering all my knowlege is gained though experience and bits of information I have picked up over the years, some of it may well be wrong but I would allways advise newbies and the like to do research add up the sums and if they are unsure think of an alternative.

we as caravanners with all the legislation piled on us MUST allways go by the lowest figure WHATEVER it is in order to be safe and legal, if a van looks too heavy for your car on paper then it probably is, fiddling round with a bit of weight here and there will make no difference.

colin

 

[Lutz]

I understand the issue that you are referring to about potentially exceeding the GVW if you put too much into the car, but fact is that so long as are sensible about it and do not overload, more payload in the car and less in the caravan will always benefit stability. Calculated weight ratio is based on kerbweight which is a worst case scenario and is unlikely to occur in reality very often and it certainly won't reflect the actual condition once you've put stuff in the car's boot.

Most family cars have a payload margin of around

 

[Steve L]

Lets not get hung up on mythical cobblers here or personal interpretations.

I'll deal the cold hard facts.

Steven has stated he is a holder of a LGV (HGV1) license and has towed drawbar trailers of heavy goods nature (wagon & drag).

His car has a tow capacity of 1700 Kgs.

The caravan has a max all up wieght of 1445 Kgs.

Looking at those two figures, the match is perfectly legal.

Now all Steven needs to do is to take his car & caravan to a weighbridge and having full fueled the car and loaded it and the caravan and got all occupants in the car, weigh it. This weight is called the "Gross Train Weight". The figure for this will be found on the VIN plate attatched to the car, and it will be the highest figure quoted in Kgs.

As Steven is a HGV driver he is well versed in looking at plating certificates in his lorries (sory mate for teaching you to suck eggs)and will be able to translate his car VIN plate accordingly.

As Lutz quite rightly said most car manufacturers "try" to publish the weights and towing info clearly. But for folks like me who drive Renault's this can be more difficult to sort out. But having been a HGV1 driver myself and having run a transport operation, I'm quite savvy with weights and measures.

Of coarse my knowledge can be a handicap as I go right to the limit of towing with my car and a little beyond. Yousee, the caravan I tow is 36Kgs overweight for my car should I load it to the max capacity. But of coarse me being me, I put that 36 Kgs plus more into my Laguna estate as it has a load capacity of 500 Kgs with the back seats down. But as we are two adults plus a 40Kg chocolate labrador (who takes over the boot), I restrict myself to putting the awning in it's bags and the poles on the back seat. Oh of coarse for safety's sake I use the rear seat belts to sucure the bags incase of accident, as I don't want a 975cm 10ft deep Inaca awning, annex and steel poles tapping me on the head should I have to stop quickly or worse still have an accident. The latter is probably going to be a rareity, as I am ROSPA and IAM trained, but qualifications on paper are worthless if you haven't got your thinking head on!!

Steven I'm sure that you will be able to handle the outfit as you have nodoubt had to drive an artic empty and you have probably like me had to work your way up through the yard hacks before you get the luxury of air suspension etc.

Good luck mate.

Steve L.

 

[ProfJohnL]

hi all,

john L "The criteria are the cars axle loads. If you fully load a solo vehicle, and then add the nose weight of a trailer you have over loaded it"

that is exactly the point I was trying to make, the assumption as I read it was that it was ok to remove weight from the van ie heavy objects like awnings ect in order to reduce the vans overhall mass and carry them in the car. without regard for the weight allready carried by the vehicle.

the maximum gross vehicle weight has a top figure for a fully loaded car "solo" that is unladen weight plus passengers and a resonable amount of luggage, unless the said vehicle is actually weighed on a weighbridge in this state it is impossible to know how much weight it is actually carrying before the trailer is hung on the back.

my point was that a car (not a hummer ect) may well be almost at it's limit once you have filled the tank,added the weight of the tow bar and filled the 5 seats put two dogs in the back hamper for the journey and filled the roof box with golf clubs fishing tackle ect, and then found room for the awning and poles (non european type) before hanging on its trailer and 75kg of nose weight. "get the picture" I did???.

ok, so if you dont have a roof box to fill, don't have any dogs to transport, no,passengers on the rear seats ect then maybe it is ok to put the awning on the rear seat and a bit of kit in the boot,

But was not inferred to by the posts.

I do not, (unlike some on this and other forums) have a background in engineering all my knowlege is gained though experience and bits of information I have picked up over the years, some of it may well be wrong but I would allways advise newbies and the like to do research add up the sums and if they are unsure think of an alternative.

we as caravanners with all the legislation piled on us MUST allways go by the lowest figure WHATEVER it is in order to be safe and legal, if a van looks too heavy for your car on paper then it probably is, fiddling round with a bit of weight here and there will make no difference.

colin

Hello Colin,

Thank you for clarifying your point, It seems we all agree about the principal, there was just some confusion about the way it was expressed.

 

[ProfJohnL]

GTW is invariably less than the combined MAM's. Usually GTW is the max. GVW plus the max. permissible towload.

Agreed, I should not have used MAM without qualifying that it matched the tow vehicles max. permissible towload.

 

[colin-yorkshire]

hi all.

john L wrote "Now all Steven needs to do is to take his car & caravan to a weighbridge and having full fueled the car and loaded it and the caravan and got all occupants in the car, weigh it. This weight is called the "Gross Train Weight". The figure for this will be found on the VIN plate attatched to the car, and it will be the highest figure quoted in Kgs."

I think I suggested this in my last post, however it has one inherent problem that is the van has to be bought first in order to weigh it""

should things then turn out to be no so "hunky dory" once the cash has been handed over "it is too late"

john like you I tow with a renault (ok it's smaller and so is the van) that in it's self makes me accutely aware of how critical weight issues can be: my outfit for example is a 98% match and with everything loaded "and weighed" is only 35kgs under the G.T.W the unit however tows fine and never gives me any worries, would I recommed it for everyone "no way" but then I do have 35+ years of towing under my belt and learned a few things along the way.