modern vans all appear nose down when towing.

[AnthonyNornIreland]

Is it just my imagination, are do all modern vans appear to tow nose down.

I had a 94 challenger, that sat level when towing, but my Ace jubilee seems to sit nose down, but the A frame is level, is it the new design, ie the rear of the van seems to curve upwards, as if to clear road calming ramps, etc. or my imagination.

I have seen other new vans, even those being towed with 4x4s and they look this way also.

For you info, my nose weight , loading etc is all correct.

 

[Lutz]

As vans are getting bigger, heavier and longer, their back ends have had to be raised in order to get enough ground clearance when the van is fully laden and the suspension compressed, as you surmised. However, the front can't be raised by the same amount because of the height of the towball which must remain where it was. Hence the nose down appearance.

 

[forestgump]

the nose down look dose rise when pulling along with air flow and weight trasnfer ontow car

 

[ProfJohnL]

Hello Dean,

Yes I agree there must be some effect, but exactly how much?, and whilst the caravan may change its effective nose load under driving conditions due to the aerodynamics of the caravan, the car also has its own dynamic effects, and how they both interact is very difficult to predict.

 

[Lutz]

Is there an issue here? I can't think of any particular disadvantage of the caravan being nose down.

 

[trucker]

We have a swift group van and yes you are right they do appear to be nose down. If you look at the skirt it almost dissapears on the swift as you get closer to the rear sugesting it is higher at the rear.

I must say though that this van and the last one (2009 and 2006)have both been hard work to get the nose weight to the correct figure, to the point on this van we travel with the cloths in the w/robe at the rear, the bedding in the shower at the rear and the most heavey stuff on or just behind the axle. this does work but throws out the theroy that you shound not load behind the axle!!!

Kevin

 

[Steve L]

I too have a swift group van, an Abbey freestyle 540se. I have also found that we have to load the rear of the van to achieve the 75Kg nose weight requirement of our 1998 Laguna estate.

When I first got the van, i thought we should be wary of loading the cavenous fixed bed storage, but we have to load that with boxes of clothes and then stack our food tin boxes next to the shower area. All this load is behind the axle. We put the awning bag over the axle. The front locker has to be kept as light as possible, with the twin 7kg gas bottles and little else. Then we just about get the nose weight right.

As for the aerodynamics, the modern van is much higher off the ground than the early 90's vans. Also you now have a much longer body on a single axle these days. Hitch heights on cars have not risen, in fact they have got lower too. All of this then leaves a van looking back high, which is an advantage on the ferry ramps. I personally think that the tilted roof look of the van produces a down force on the van, which inherantly add's to stability in a simlar way as an aerofoil on a race car. Now because the roof angle is spread both fore and aft of the axle, the air pressure effect is balanced out.

steve L.

 

[xtrailman]

I don't knew if a 2004 van is considered modern, but my xtrail does now tow nose down.

But that's only because witter have made the tow ball height about 1" lower for my 2009 xtrail, previously my 2004 xtrail, with the witter bar, towed level.

And towed a lot less twitchy, but that could be car related, rather than tow ball height related?

 

[Lutz]

Steve, hitch heights haven't got lower, at least not in the last 15 or more years. The EU directive for hitch heights has been in force since 1994.

 

[Guest]

I agree many vans appear to have a nose down disposition, but I do not see any connection with van design. If I look at my 2005 model there is a straightline from the front right to the back and when hitched this straight line continues into the tow vehicle. However, this is dependent on an number of factors. Tow hitch height being one, rear suspension being another and what I feel could be significant in that many vans particularly from the UK have the axle further to the front of the van than those from elsewhere. I always have believed that the relative distance from front of van to axle and then to rear should be greater than 1, but often this is not the case. This I feel tends to accentuate any other 'discrepancies' in tow hitch height etc, and gives a more pronounced down word look.

 

[Guest]

I agree many vans appear to have a nose down disposition, but I do not see any connection with van design. If I look at my 2005 model there is a straightline from the front right to the back and when hitched this straight line continues into the tow vehicle. However, this is dependent on an number of factors. Tow hitch height being one, rear suspension being another and what I feel could be significant in that many vans particularly from the UK have the axle further to the front of the van than those from elsewhere. I always have believed that the relative distance from front of van to axle and then to rear should be greater than 1, but often this is not the case. This I feel tends to accentuate any other 'discrepancies' in tow hitch height etc, and gives a more pronounced down word look.

To clarify, when I state 'van design' I mean shape of body panels.

 

[Lutz]

Assuming a more or less uniform weight distribution, if the axle is further forward than you would expect, as you mention, Scotch Lad, then the noseweight would also tend to be lower. However, particularly with UK caravans, this appears not to be the case as many owners complain about excessive noseweight on their vans when empty. The only conceivable explanation that can then be offered is that the caravan designers are not doing their job properly in maintaining a good weight distribution of the van in its ex-works condition.

 

[Steve L]

I'm well aware of the tow ball height regs Lutz, but what I'm getting at is the simple fact that tow ball heights are getting closer to the minimum height.

Car designers are working with the tow bar manufacturers to make the tow bar more of a design attatchment rather than a practical feature. With the advent of the detatchable tow bar, I would of thought that the practicallity and functionallity of the tow bar was more of a priority, as one can take the bar away in seconds to return the tow car to it's NCAP tested state and compliance with EU construction and use regs.

My previous van a 1982 Link 575 was a very low slung van and I grounded that on the Red funnel ferry both on the A frame and the rear of the van while boarding the ferry. My current van a 2005 Abbey 540, would never ground on the rear but the Jocky wheel would no doubt ground out as it has been fitted as a combination of the tow hitch, and is not easily removeable. I am actually going to fit a secondary jocky wheel clamp to the outside of the A frame so that I can fit my Motor mover ET. I also intend to fit the standard jocky wheel there so that I can remove it while the van is hooked to the car, to avoid both the grounding possability and also the physical look of the van being too close to the ground.

After all, our friendly "interplods" use the "looks too heavy" excuse to stop and check the outfit, rather than rely upon a breach of road law to pull a driver over. My tow car doesn't help either my Laguna estate doesn't sit rear end high like most estate cars but it sit's flat and level giving the impression that the boot has it's full 450Kg payload on board. You see, it is the sport version of the estate with stiffened and lowered suspension to complement it's 140BHP performance.

 

[Dustydog]

Now I am confused but not dot com!

On an earlier thread in regard to measuring nose weights a number of you were adamant that the caravan must be absolutely level in order to avoid an inaccurate reading.

Does this mean that those towing in a nose down attitude could unwittingly be doing so with the wrong nose weight??

Cheers

Dustydog

 

[Steve L]

Good point Dusty.

There will be some added weight as the caravan is towed in a different attitude to when it was measured. The error might be small but the affect could be amplified.

So I would recomend weighing the hitch weight with the hitch at the normal road towing height for greatest accuracy. I use a hith measurer that fits between the hitch of the van and the towball of the car. This does lift the van hitch about 50mm above normal, but that is close enough to give a reliable reading. If I were to weigh my van sat level, the hitch would be a further 150mm above that.

ATB

Steve L.

 

[Guest]

I think the main issue with excessive nose weight when empty is indeed design and the fact that UK manufacturers insist on using a shorter A Frame. I cannot see any logic to it all except the desire to sell as much van per length. I suspect that in many cases, the manufacturers do not actually measure the nose weight of their products, but just add the ALKO recommended weight to their own plate.

There is also a desire to pack as much volume as pssible into a given chassis length, and once abattery is added plus all the other paraphernalia, things can quickly get out of hand.

 

[Lutz]

The noseweight should be measured on level ground, but NOT necessarily with the caravan standing level. If the caravan is nose down when hitched up, then the noseweight must be measured with the caravan standing the same way.

That the towball height is close to bottom limit is actually a sign of good design, as this height is measured with the car fully laden. If the car is towing with anything less than its full payload, the towball will, of course, be higher (unless the car has self-levelling suspension).

 

[Heethers]

On my Shogun tow bar l have to heights the lower one that it is set to at the moment, which has the van slightly nose down.

l have judge by looking at the set up that if l use the upper setting on the tow bar l am sure the van would be level, do you think it would be better to have a level set up than slightly nose down.

The rig tows fine as it is now, but l find especially when negotiating speed humps the jockey wheel grounds sometimes depending on the height of the Humps.

The distance between the settings is 25mm. or 1" for us oldies.

 

[Lutz]

Offroad vehicles are exempted from the regulation that the centre of the towball must be between 350 and 420mm above the ground when the car is fully laden. That's why they often have optional adjustable heights.

 

[colin-yorkshire]

hi all

I dont know if this is relevent to the discussion on van design but our bailey 380 has a shipping lenth of 5.25mtrs the distance from the centre of the tow hitch to the centre of the wheel is 3.55mtrs and the front of van to centre of wheel is 2.55mtrs ie 1mtr of A frame. from the side of the van the wheel definitly looks towards the rear giving the illusion the van is nose down when it is not " a bit like starkys torino" the high back end does not help this. however the 420 which is basicaly the same van with end washroom has almost the same mesurements so looks level with the wheel in the middle.

I assume therefore that the designers at bailey have done this (put the wheel off centre) because all the heavy items are behind the wheel "toilet with flush" cooker,fridge, heater ect and the extra front length of the body assists it's nose weight by balancing out these heavy objects.

 

[WatsonJohnG]

The wheel size has increased recently with Swift fitting 15 in wheels against Bailey 14 in and for many years 13in were the norm

This may have some effect on nosedown-ness if no modification has been made to chassis and suspension to compensate

I am very aware on the motorway of many very nose down looking outfits and to my eye it may be right but it doesn't look it!

 

[Lutz]

I am a bit surprised that this topic has become such an issue. Just as there is a standard height for towballs on towcars (between 350 and 420mm to centre of ball when the car is fully laden), the regulations also state that the hitch on the caravan shall be between 395 and 465mm above the ground when the caravan is fully laden and standing level on level ground. This, by definition, already results in a nominally nose down attitude that would be increased further if there is little or no payload in the caravan.

 

[WatsonJohnG]

Lutz

I couldn't agree more

I am currently emptying the van prior to changing and so far about 1/2 empty the rear steadies are now well clear of the ground as the suspension rises

 

[Steve L]

I'm not suprised at all that this topic has been so popular.

While Lutz is technically correct as usual, ther is a wider debate here about the perception of the physical look of the towing outfit. This "look of the outfit" is arguably the initial impression that attracts the attention of the rozzer's. This is understandably concerns those of us who are novices or even the seasoned tower who is towing at full capacity of their tow car like me.

The other perspective is that of stability. After all. if the caravan roof line is slanted like a giant aerofoil, then is that going to have an adverse affect on stability of the tow car? Having said that, you would have to be travelling at or above the max permitted speed before any affect would be decernable. However is you are driving a car that has rear steering suspension designed to enhance it's cornering and this is worn out, then you may be at a greater risk of instability.

Tow ball height does matter. With the ever increasing desire for a larger jockey wheel for ease of manouvering, the distance between the tow hich and the bottom of the same said jockey wheel is ever increasing. Now couple that to a towball of the lowest height permissable and you have got a possable grounding issue. Also, you have a hitch that "looks" seriously low.

Steve L.

 

[Lutz]

Both towball and caravan hitch heights have a tolerance of 70mm, more if you take into account that car and/or caravan are not fully laden. With one on bottom limit and the other on top limit, it is unavoidable that the caravan can have both a nose down or even, in the opposite case, a slight nose up attitude. Unless both car and caravan have a self-levelling suspension it is something one just has to live with, but which does not have any technical disadvantage. The effect on stability is negligible. Unless the caravan were to appear as if it were standing on stilts, if you don't have a grounding issues at the jockey wheel, you'd have a grounding issue at the back.