Thread: Tow Ball Download weight confusion with state legal

Originally Posted by discomatt69

I think that is to allow for the moron factor and people putting way to much pressure on them, Jeeps with the same air suspension set up have no issues using a WDH

I remember reading an investigative report by a large, Australian, towing company, into caravan accidents, which basically stated that " If a WDH is required, then: 1) The tow vehicle is unsuitable. 2) The van is unsuitable. 3) The cargo distribution is incorrect. ".

Originally Posted by Saitch

I remember reading an investigative report by a large, Australian, towing company, into caravan accidents, which basically stated that " If a WDH is required, then: 1) The tow vehicle is unsuitable. 2) The van is unsuitable. 3) The cargo distribution is incorrect. ".

this is an idealistic take, id prefer to not use one simply from the point of view of it being less gear and process to hook up.

but from a functionality point of view, they do actually work and are very popular and i see them on every brand of car.

a car will inevitably sag with added weight on the rear, and reducing this sag helps with handling and axle loads.

i think its also a problem that Australian caravan manufacturers seem to build very front heavy vans compared to their european counterparts.

they also smooth the ride by stiffening up the joint where the hitch is, which normally needs to pivot, but can have benefit to resistance of such in the up and down direction compared with the side to side.

smoothing out bounciness is a big safety plus

sure they can be used in situations where something else should be changed, and they might be over represented in accidents, as these are people that might be near their limits, but there is a huge range of legal towball weight allowance for any car and van combo, this is just another way to let you adjust it, while having added benefits as mentioned

Originally Posted by haydent

I dont think it is mentioned anywhere, and its just a old wives tale that you cant use them. There is nothing special about them that the suspension would even experience or have to interact with, all it does is change the load experienced by the axles by making a stiffer joint at the hitch.

no different to just having a heavier or lighter tow ball weight through normal means

Nup. Right there in the handbook. Page 190: An equalising or other form of weight distributing hitch should not be used with your vehicle.

Towing WDH.JPG

ah thanks for that, i stand corrected, i was searching for different words than what they used. pity there's not more detail there as to why, if they think its just not necessary or something else

Originally Posted by haydent

ah thanks for that, i stand corrected, i was searching for different words than what they used. pity there's not more detail there as to why, if they think its just not necessary or something else

No probs. I've been rummaging through the workshop manual, but it doesn't rate a mention.

Originally Posted by haydent

ah thanks for that, i stand corrected, i was searching for different words than what they used. pity there's not more detail there as to why, if they think its just not necessary or something else

The Why is that the suspension will continuously fight the WDH causing issues rather than solving them.

The vehicle measures load, think inline with how it knows it's grounded offroad and goes to super extended - it's the load measured inside the bag (pressure) and keeps trying to return to spec.

WDH are a band-aid. The added stresses on the frame and hitch point are quite crazy.

As another mentioned - a well set up combination won't need them. Our 24? van certainly doesn't.

I certainly don't need a weight distribution hitch but what do need is a GVM upgrade because the car handles exceptionally well, tows fantastically and feels safe and stable along with good servicing and maintenance there are no issues other than the legality of numbers?

Originally Posted by Tombie

The Why is that the suspension will continuously fight the WDH causing issues rather than solving them.

The vehicle measures load, think inline with how it knows it's grounded offroad and goes to super extended - it's the load measured inside the bag (pressure) and keeps trying to return to spec.

WDH are a band-aid. The added stresses on the frame and hitch point are quite crazy.

As another mentioned - a well set up combination won't need them. Our 24? van certainly doesn't.

the vehicle does not measure load at all, id thought it wouldnt be hard for it to be able too with a few more pressure sensors, it could give you axle load numbers by measuring the air bag pressures.

(it only has one pressure sensor to measure the reservoir pressure)

it works out the extended mode from the height sensors, and if it cant lower itself

the WDH hitch itself balances out the force from the smaller upforce of the bars and the greater trailer downforce , the result of this is then experienced as less downforce on the receiver. the bars also put pressure on the a frame

the only reason im using one is to move weight off the rear axle, you wouldnt think you needed one otherwise with self levelling suspension as it will hide the overloading of the rear end

The Effect of 4 Corner Auto Leveling on a Weight Distribution System

https://www.youtube.com/watch?v=mj2oqAiltsk

Originally Posted by discomatt69

I certainly don't need a weight distribution hitch but what do need is a GVM upgrade because the car handles exceptionally well, tows fantastically and feels safe and stable along with good servicing and maintenance there are no issues other than the legality of numbers?

i think youll find you will go over your rear axle limit before the gvm one (the opposite problem of a 200 series lc)