POLY AIR BAGS.

Paynie,
I have had poly-air bags on a range rover for towing a big boat, and now I run them on my prado, my mate on his 100 series, and another mate on his 80 series and have done some rough trips outback and they have been great, so good luck with them
Peter

paynie, I forgot the costs, last year it cost my mate 300 dollars fitted to his 100 series, my prado $280

cheers Peter

I have had poly airs on my 80 series since 1991 - 14 years no trouble with them. Have done lots of desert 4wding and caravan towing over those years. They are a great help with van towing and vehicle levelling, its the best $300 I have spent.

cheers

Paynie,

I have towed heavy vans with different vehicles for years.

It is a heavy van and you must get a load distribution hitch FIRST and a check of the load going onto the ball when the caravan is loaded.

The load distribution hitch shares the load through the whole rig and evenly across the vehicle. Polyairs or other spring support in the back (w/o load distrib. hitch) does nothing to redistribute loads - overloads rear, takes weight off front (the steering end) and could conceal caravan loading problems and ball overload. This means you could have a high likelihood of a high speed accident.

It is a real problem that many dealers who sell aftermarket springs etc know nothing about vans.

However people like Hayman Reese manufacture and market towing systems and give competent advice:
link text

It is always a good idea to run the vehicle and the fully laden van (water tanks full as well) over a weighbridge soon after acquiring the van. You could just call in when on the way somewhere. It is money well spent if they check the weight onto the towball and the van weight. Just changing the load in the van could save you a possibly irrecoverable sway at speed, or a nasty surprise when the van gets loose on the verge of a road.

Have fun
EV700

Member - ALLAN P (QLD)
poly air bags are great they make the rear take a extra 500 kg and lift the coil springs to help they are worth the money

I agree with EV700. Polyairs won't really help with towing the van. They might bring the back of the truck back up, but they won't distribute the weight evenly over both axles. I'll bet that if you measured how much the back end drops and the front end rises, then adjust the polyairs up to level the back, the front end will not go back to where it was. Lots of people make the mistake of thinking that stiffening up the rear end helps, but it does nothing for putting an even portion of the extra weight of the towball back on the front axle.

I have polyairs for the weight in the back, but I used 250kg HR bars for towing my van with a 200kg towball weight (measured).
regards

Andrew

atoyot,
True story mate, you must use a good WDH, my van is similar and has a ball weight of around 200Kg and the polyairs do assist with keeping thberear up a bit. They seem to stop bottoming as well. I run with about 20psi with the van in tow.
Incidently they DO NOT increase the load carrying capabilities of the truck. In fact there is a statement in the installation instruction saying just that.