In Short No! Except where a manufactures says one is required for a particular model towing over certain weights etc. Personally though I wouldn't tow my van without one or purchase a vehicle that prohibits the use of a WDH The use or non use would usually depend on what you're towing and what the tow vehicle is. Ozjohn.
-- Edited by ozjohn on Thursday 31st of January 2013 11:58:36 AM
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Retired Engineer, Ex Park Owner & Caravan Consultant. Holden 2.8 Colorado - Roma Elegance 17'6" Pop Top. Location: Mornington Peninsula Vic.
On my last trip I saw a newish Range Rover Sport pulling a van round 21'6" .. estimated at 2.3 ton therefore around 230kg ball weight.
He didn't have a WDH!
Unfortunately we left the CP early & I didn't get a chance to talk to the driver about the set up.
A friend who used to tow with an old Rangie, thought that the 'intellegent' air suspension auto adjusted the set up to compensate for the extra ball weight.
Looks like I might need to do a bit of research.
I too would always use a WDH whether it is compulsory by law of not.
The following is from an RACQ article "Tech Tips on Towing". It is a simple to read explanation of "weight distribution hitches" & their purpose.
Call them level-riders, load equalisers, stabiliser bars, anti-sway bars, weight distribution hitches and the like, many people do not understand what they do and how they work.
When towing a caravan or trailer, the ball weight plus more is placed on the rear wheels of the vehicle. So attaching a caravan pivots the weight on an axis (the rear axle) and raises the front wheels, making steering lighter and braking less effective. With front-wheel-drive vehicles, traction can also become an issue.
Use of overload springs or pump-up shock absorbers to raise the rear end may make the whole vehicle ride higher, but they have no effect on weight distribution whatsoever.
Just because a towing unit is level, do not assume it is necessarily going to tow correctly and safely.
Fitting a weight distribution device of the correct size and type means that the tow vehicle becomes level, weight is transferred back to the front wheels of the tow vehicle, and some weight is transferred back to the caravan wheels, thereby minimising steering, braking, traction and sway problems