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Quote: Originally posted by ericmark on 22/8/2018

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Tow bars have to comply with set standards so does not really matter what make they will all comply.

So the only difference is what they look like, with some cars the ball can be quickly removed so you don't know the car has a tow bar.

Electrics is some thing else, there are two basic types, 13 pin and twin 7 pin, depends on age of caravan.

Then there is what you want to be powered in the caravan when towing. You can get.
1) Reversing lights only.
2) Non ignition supply.
3) Ignition supply.
The latter it seems changes according to caravan towed, with no charging in caravan there is no need for split charging diodes or voltage dependent relays, with a DC to DC inverter in the caravan again nothing special needed in the car.

However if the caravan connects the caravan battery to the car battery to charge the caravan battery without using a DC to DC inverter then some other method is required to stop the reverse happening and the car using the caravan battery.

With a car with a simple alternator the voltage dependent relay does a good job, however this is not the case if the alternator is controlled by the cars engine management, it would need a blocking diode to stop reverse current as you don't want a voltage dependent relay dropping out as it would stop the electric anti-snake from working.

However a blocking diode was never really successful charging the caravan battery, so likely better having the caravan battery charging disabled.

When I use to tow many trailers the electric anti-snake did not exist, today one would not worry if the trailer towed did not charge its battery while being towed so one would fit blocking diodes, that ensures anti snake works.

However if you then want to tow your own caravan you would need to by-pass the blocking diode so there was reduced volt drop so it would charge using a DC to DC inverter. OK commercial but you would hardly want a blocking diode fitting if after you are going to by-pass it.   

First question is does the Navara pickup have the alternator controlled by engine management? If not simple voltage dependent relay will do. If it does then next question is what will the caravan being towed have? Can it be easy stopped from trying to charge battery? My caravan just needs one fuse removing, are you going to pay out for a DC to DC inverter.

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Quote: Originally posted by Rob and Tina on 22/8/2018

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I don't know the year of your truck Jakki but I suspect that you can only get a fixed flange tow bar for it and you need to make sure it has an Alko extended neck tow ball to accomodate the Alko hitch stabiliser that your caravan will probably have. Google Alko tow ball to see the difference against a standard tow ball.

With the electrics you have a choice of 7 pin or 13 pin electrics. If you have 7 pin you need twin sockets to enable the fridge to work and the battery to charge whilst the caravan is being towed. If you have 13 pin electrics all the electrics are connected with one socket. I would just ask the fitter for his advice but I would go for 13 pin and if the caravan has twin 7 pin sockets I would get it converted to a 13 pin plug, this would also future proof your set up if you got a newer van in the future.

Ericmark's post is very interesting but I feel it over complicates the situation.

Rob

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Quote: Originally posted by rustyfrog on 22/8/2018

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All good advice from the posts above.
Just to add that there are two common types of caravan hitches which may be an idea to google.

The Al-Ko hitch is a fat thing that requires more distance between the rear bumper and the tow ball, therefore a longer swan neck.
Mine is a bit short of being comfortable, but I manage.

The other common modern hitch is the Winterhoff. Does much the same thing as the Al-Ko but is of slimmer design and dosent need as much room.

If in doubt when ordering the tow bar/ball get the extended one.
It will suit both.

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Quote: Originally posted by Rob and Tina on 22/8/2018

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Jakki, have a look at the Witter tow bar website, you can put your registration number in and it will show you what they can supply and give you a price for fitting as well.


Rob

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Quote: Originally posted by Rob and Tina on 22/8/2018

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Although it's dearer than you expected it's still fairly reasonable these days. Mine would have been about £700 but luckily I didn't have to pay for it.

Now you have an idea of cost it's worth talking to your local fitters and getting a few quotes.

Rob

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Quote: Originally posted by richardandjo2010 on 01/10/2018

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A good fitter will be able to advice you best, personally I prefer detachable so you don't bang your leg on it when getting items from the boot, judging by your new van you got you will need 7 pin sockets. I don't know March towbars but I have used MB towbars from Ipswich twice now and I have been most pleased with price, service and knowledge, he is also mobile and I am sure he covers your area may be worth a call

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