I thought this might be of use to some people on here.
I bought my very first caravan in October last year. Some of the guys on the Yeti forum of Briskoda (that both lurk here as well! ) pointed out that my mature van was towing very much nose up:
At first this did not bother me until I read this:
Under heavy or emergency braking, there could be enough force acting on the rear of the towing vehicle to reduce the weight on the rear wheels sufficiently to cause the rear wheels to lock and lose nearly all braking effect, if the caravan is also slightly out of alignment with the towing vehicle the combined effect of the lateral pushing of the vehicles rear will reduce further the efficiency of the caravan braking (over run) action increasing the force acting on the vehicle and this will quickly escalate pushing the vehicle further sideways resulting in a “jack-knife” It is essential therefore we tow with the caravan slightly “nose down” and here’s why.
Under braking, the direction of force acting on the towing vehicle from the caravan will be in a slightly downward direction, increasing the load on the rear wheels of the towing vehicle. We know from above, under heavy or emergency braking that the center of gravity of the towing vehicle moves forward and pitches the nose down increasing the load on the front wheels and reducing the load on the rear wheels.
By towing “nose down” when braking, the caravan’s acting line of force, resists this and imparts a further downward acting force onto the rear wheels and effectively increasing the grip on the road surface. This has two advantages: firstly, it will resist any tendency for the rear wheels to lock up as the increased grip will resist the force of the brakes and keep the wheels turning, improving overall brake efficiency of the vehicle. Secondly, if the caravan is out of alignment with the towing vehicle, the increased grip will help resist the lateral force imparted on the rear of the vehicle that wants to push it sideways, therefore reducing the chances of “jack-knifing”.
So I put my thinking cap on. I did not want to change my £834 Westfalia towbar as that was daylight robbery enough. Then I started thinking about other cars with Westfalia detachable towbars thinking they must have the same coupling mechanism and looked at videos of these on YouTube. The VW Tiguan looked a prime candidate:
Yeti towbar:
Tiguan towbar:
Images combined:
A quick search on eBay for images of a Tiguan towbar yielded a used Tiguan towbar for £20 plus postage! I was in the right place at the right time.
Before:
After:
Side by side:
And voila!
A perfectly level caravan behind my Yeti (which is pictured on its winter tyres which are slightly bigger than the summer tyres. So on the summer rubber and with some weight in the boot the van will be even more level).
Hope this was of some use to someone with a similar predicament.
Post last edited on 10/02/2014 16:46:26
------------- VW Touareg 3,0 R-Line + Swift Sterling Elite 580
Well done in sorting out the problem but surely you were sold the wrong fitting in the first place.
£20 for a fix and posting on here is great, and your info will im sure be of use to others.
Great on here init
Tow balls should have a height of 350 to 420mm with the vehicle laden so I was wondering if the original tow ball height was within this range. If the height was outside the range then the tow ball design was wrong. Is the tow ball height with the new ball within the height range?
What is the coupling height of the caravan? It should be 385 to 455mm when the caravan is laden. If the coupling height is low the the suspension may have sagged as Grampian suggested.
Quote: Originally posted by Rob and Tina on 11/2/2014
Tow balls should have a height of 350 to 420mm with the vehicle laden so I was wondering if the original tow ball height was within this range. If the height was outside the range then the tow ball design was wrong. Is the tow ball height with the new ball within the height range?
What is the coupling height of the caravan? It should be 385 to 455mm when the caravan is laden. If the coupling height is low the the suspension may have sagged as Grampian suggested.
Rob
I'll check the van's suspension but it is fine now with the lower towball. And I suspect my £20 fix was cheaper and less hassle than fiddling with the suspension on such an old caravan!
As to the height of the towball, what you quote is to the CENTRE of the ball. Add say 40mm for half the ball and my Yeti's height should be between 390mm and 460mm.
The factory approved Westfalia is slightly higher than those limits albeit not much:
That reads about 477mm
And the Tiguan towbar:
That reads about 402mm
So by fitting the latter I dropped my towball by a decent 75mm which solved my problem.
------------- VW Touareg 3,0 R-Line + Swift Sterling Elite 580
A day of all things motorhome and campervan. The show is held both in the main indoor arena and across the grounds. Catering, hot drinks and food options are available. Easy access to the site and free parking included. Win one of five pairs of day tickets