Tech Talk: Q&A

AIRBAG DEBATE

Hi CW,
Some folks tell me that they have rear airbags on their tug and therefore don’t need a WDH.
I thought they did different things and even if you had airbags, if the rear of the vehicle drops by more than 20mm, a WDH is worth using to restore weight back to the front axle.
Could you please give me some info on this? Which of us is correct? I appreciate your response to this query.
Sally Jones, via email

Hi Sally,
Here are my thoughts...
When towing, the best scenario is to have the complete rig (vehicle and caravan) as level as possible.
Airbags in the tow vehicle can be used to help with rear suspension sag when you are towing your caravan, but only to a point. If you put crazy pressure into your airbags to stop the rear suspension sag when towing, then you may have very limited rear suspension travel in the vehicle and that would be extremely dangerous (there is also the high possibility that you will break something very important in the tow vehicle as the pressure on the diffs and chassis would be extreme...).
So, depending on the caravan towball weight and the vehicle in question, the use of airbags may be enough to level out the rig (provided you don't need to go crazy with airbag pressures) and therefore you don't need a WDH.
So in response to you Sally, I'd say that both of you are correct. Depending on towball weight and the vehicle you could just get away with airbags but in other cases you may actually need both... or just a WDH.
For me personally, I would try to make sure that I buy a caravan that matches the towball weight of my vehicle (ie doesn't create the rear suspension sag), and try to avoid going down the road of airbags or a WDH.
Micah Brouwer

BREAKAWAY REQUIREMENTS

I have a Roadstar caravan built in 1992 with a GTM of 2200kg. The van was not fitted with breakaway brakes because of the year it was made, so am I excluded from using this system or can I get them fitted? Thank you.
Martin Humphries, via email

Hi Martin,
No, you are not excluded from this system. In theory, to get your van registered, it should have a breakaway system fitted.
Hooking up electrical brakes to a breakwater unit is actually quite a simple process, not forgetting of course, that if you are in NSW then a battery monitor will have to be fitted to the tow vehicle as well.
Malcolm Street

A WEIGHTY ISSUE

After more than two years of research, which included reading your magazine, we have finally placed an order for a Crusader Recliner caravan, fitted with the AL-KO ESC system.
However, our tow vehicle is a 2013 D40 Navara, and I have been getting conflicting information on whether I will need a weight distribution system and/or beef up the suspension on the Navara.
Any help would be appreciated.
Paul Cassells, via email

Hi Paul,
You don’t mention any weights, but I reckon that a weight distribution hitch is better because it shifts the weight to the front wheels. Beefing up the suspension does lift the rear of the tow vehicle, but it can also give you a firmer ride
Keep in mind here that some hitches aren’t suitable for weight distribution bars and some tow vehicle manufacturers don’t recommend use on their particular vehicles.
Malcolm Street

KEEP THE JEEP?

I have an Adria Adora 612 and when I started towing with the Tuson, she towed like a dream. Obviously overweight though, I've just bought a 2015 Jeep Overland.
Prior to buying, if I ever saw a Jeep and a van I would head straight over to talk to the owner, and not once did anyone have a bad thing to say.
Now, the Adria and Jeep hate each other. Up to 80km/h I feel fine, at 90km/h I'm hanging in there, and once I hit 100km/h it's a struggle. I feel like the front of the car isn't grounded, and when passing almost anything I feel it all and hang on for dear life.
Everything appears even in terms of ride heights, and if I turn traction control off on the car, it stops fighting as much.
But I have gone from enjoying the tow and the destination to hating it, which is not good considering we go out most weekends.
If I can't find an answer, the Jeep is for sale.
Hope you have some tips.
Jay Bingle, via email

Hi Jay,
From your letter I presume you have a Jeep Cherokee Overland, which has the 3.0 litre (177kW/550Nm) turbodiesel.
Given the Adria Adora has an ATM of 2000kg or 2130kg, if you have the Sport model, then you should not really have a problem.
I must admit to being a bit mystified. If you feel like it’s a handling issue, then could I suggest you measure the loaded towball mass to make sure that is within the Jeep’s specifications.
If you can borrow a different vehicle to see how that tows, it might be helpful.
Otherwise my only suggestion for you, keeping in mind your comment about traction control,
is to get your Jeep checked out to be entirely sure that everything that is related to towing — suspension, brakes and any safety features — are all operating correctly.
Malcolm Street