Towball - Udjuster plates - Why down only

[sshortcircuit]

Have just acquired a 4 wheel trailer and when positioning it to the tow ball it looks as though the ball could come up an inch. Looked at suppliers of plates and they all say that plate is for lowering only Why is this?

 

I appreciate I can get a multi level adapter at about £40 but why down and not up?

[Guest ChrisB]

Can't answer the question, but for years whilst tugging a caravan I used a plate to raise the hitch about 5cm to reduce the possibility of grounding the jockey wheel. Towed for thousands of miles in the UK and France/Spain with no problems.

Perhaps the CC Technical Dept. have an answer? Might put a greater downward strain on the towbar fixtures to the vehicle?

[lennyhb]

It is to do with the increased forces that will be applied to the mounting points fitting riser plates has always been frowned upon.

 

Car registered after August 1998 have to have type approved towbars, drop plates can be fitted to some providing the towbar manufacturer states so. Rising plates can only be fitted with written permission of the towbar manufacturer.

Certain 4x4's and other large vehicles can be fitted with a towbar that allows coupling height adjustment the type often seen on Land Rovers.

[tonyg3nwl]

Hi, I have used adjuster plates at different times and on different vehicles and which way up or down depends on getting the van level when hitched to the car, or very slightly nose down. If the nose is too high, I have always found that the stability is significantly worse.

 

Place the van on a level road and adjust jockey wheel to get the van level Then measure the hitch height into the socket. Measure the top of towball height on the car separately, and chose a plate that enables a coupling to be level. Then hitch on the van, and the noseweight will cause the hitch coupling to drop slightly to give a slightly nose down attitude of the van.. This has always been satisfactory from my experiences over 40 years plus of towing..

 

tonyg3nwl (now lugging not tugging)

 

[sshortcircuit]

Thanks very much for info. Does not look to bad so am off for the weekend and will wait and see.

[Rosbotham]

My old motorhome had a towbar fitted that defacto had an "up" plate. The towbar was of the type that had a bar across the width of the back of the van, and the towball was mounted onto a plate that rose up from it. In addition to the plate, there was a supplementary bracket that ran at 45 degrees...plate was fastened to the front of the bar, bracket came from the back of the bar.

 

It was fine when I was towing my car on an a-frame, but when I switched to a trailer for a while, it was clearly too high. I got Mick Parkinson to take a look at it, and he rebolted the towball directly through the towbar, which took it to the correct height.

 

So I guess it came supplied with an up-plate, and I removed it : opposite of what you want to do.