Confusion reins

Cee · Senior Member

Confusion reins

gold dandelion · Senior Member

we put air bags on our car nissan pathfinder, from advice and were really happy, ran into two truckie bros in tamworth, towing big vans they use bags as well, threw their bars away.

ozjohn · Guru

Cee.
Torsion Bars, level Rides etc are different names for a Weight Distribution Hitch (WDH)
These distribute weight applied to the rear of the tow vehicle.When a weight it placed on the tow ball weight is removed from the vehicles front wheels. If it's a heavy weight then the front of the vehicle may rise a little or a lot. The WDH ditrubutes the weight over the vehicles wheels so that the correct weight is maintaned on the front wheels to ensure safe steering and braking.
The type and strength of the bars depends on the weight the trailer places on the tow ball and is referred to as the Ball Weight.
The heavier the ball weight the stronger the WDH needs to be.
A Two round bar WDH will handle a Ball Weight up to maximum of 80KG.
A four bar one upto a maximum of 120Kg.
And something like a Hayman Reese 550 WDH upto 250Kg.
WDH's are sometimes referred to as Sway Bars, but that is an incorrect terminology.
A Sway Bar, or Anti-Sway Bar to be more correct, does not do the same job as a WDH. They are usually a flat bar with adjustable friction pads that assist in minimising trailer sway, especially when being overtaken by large trucks. They however should not be used to eliminate the sway effect caused by poor distribution of weight in or on the trailer and are usually recommended as an accompliment to a WDH.
Cheers, ozjohn.

jimricho · Guru

Here's a couple (pardon the pun) of sites that may be useful.....

http://www.haymanreese.com.au/products/weightdistributionsystems.htm

http://www.haymanreese.com.au/products/swaycontrollers.htm

My Pajero has "OME Off Road" suspension and "Airbagman" air bags and I do not have a WDH. The rig tows well without any stability problems.

My "Goldstream" (1350kg ATM) is fitted with a Treg hitch that's not compatible with a WDH

-- Edited by jimricho on Thursday 25th of November 2010 06:20:35 PM

PeterD · Guru

Cee - Is your van 1 tonne tare or 1 tonne ATM? On forums we prefer to talk ATM as you tow your van closer to its ATM than its tare weight.

If your loaded van weighs in at less than 1300 to 1400 kg then you probably do not need a WDH.

Jimricho - Treg hitches ARE compatible with WDH. Some of the early ones with low capacity blocks needed the block changed if they were to be used with WDH. Hayman Reese have some sort of spacer so that your vehicle mounted piece will sit properly on the ball head. The instructions tell you to take the bars off when transversing extremely undulating country.

jimricho · Guru

Thanks PeterD, I hadn't researched the issue of a WDH with a Treg as I don't need one anyway. I just assumed incompatibility and anyway it would negate the advantage of a Treg, however as you point out one can remove the bars if necessary.

My previous camper trailer also had a Treg fitted and I took that to places where I would have had little confidence in a ball hitch. As I'm not taking my current set-up to such places I'm seriously considering changing over to a ball hitch and fitting a couple-mate for ease of hooking up solo.

Cupie · Guru

jimricho wrote:

Here's a couple (pardon the pun) of sites that may be useful.....

http://www.haymanreese.com.au/products/weightdistributionsystems.htm

http://www.haymanreese.com.au/products/swaycontrollers.htm

My Pajero has "OME Off Road" suspension and "Airbagman" air bags and I do not have a WDH. The rig tows well without any stability problems.

My "Goldstream" (1350kg ATM) is fitted with a Treg hitch that's not compatible with a WDH

-- Edited by jimricho on Thursday 25th of November 2010 06:20:35 PM

Great post .. Love the reference source.

I was unaware that HR had the heavier 750lb kit that can take ball weights to 340kg. I went to my very old documentation & there it was on p6 " available in 250kg & 350kg hitch weights" which I assume refers to max ball weights. Mine is the 350 for a measured ball weight of 271kg.

(I'll bookmark that site)

With regard to the use of air bags, I recall an article by Tom Olthoff of Caravan World fame mounting an argument that suggested that rear airbags did nothing to improve weight distribution. He made the point that with respect to weight distribution, all the rear bag does is reinforce the fulcrum point and although the rear might not sag, the lever action will still try to lift the front Don't know if he was correct. There seem to be a lot of air bag enthusiasts around.

ozjohn · Guru

Quote:
With regard to the use of air bags, I recall an article by Tom Olthoff of Caravan World fame mounting an argument that suggested that rear airbags did nothing to improve weight distribution. He made the point that with respect to weight distribution, all the rear bag does is reinforce the fulcrum point and although the rear might not sag, the lever action will still try to lift the front Don't know if he was correct. There seem to be a lot of air bag enthusiasts around. Unquote

Tom is 100% correct as he was with most things we wrote.
Air Bags do not distribute weight, they only raise and stiffen the suspension.
ozjohn.

Footnote: Mitsubishi 'Recommend' a WDH be used with Pajero's.
Some models it's blanket statement for other models a WDH is recommended for Ball Weights in excess of 135Kg.

PeterD · Guru

There has been a bit in 4WD and vehicle newsgroups regarding bent chassis on single &twin cab utes. A lot have stated that air bags were in use. Others made no statement one way or the other.

When you add air bags, you are transferring the lift on the chassis from the two points at the spring eyes to a single point at the air bag. Whilst the load has not totally been transferred to the air bag lift point, it has severely changed the stresses on the chassis. The chassis will not necessarily bend above the air bag but it will bend where a newly formed (by the addition of the airbag) weak spot has ocurred.

If you want to see the difference between a leaf spring two support point suspension and a single point spring mounting, just climb under a Navara and a Pathfinder. Although there are many common items in both vehicles, the rear ends of their chassis are completely different.

-- Edited by PeterD on Friday 26th of November 2010 12:08:08 PM

jimricho · Guru

I certainly would have fitted a WDH if the need were evident. I have towed my current rig probably about 25,000 km so any need for one would have been evident by now. I have little doubt that a larger rig would need a WDH.

Yes the placard on the Pajero towbar does state a ball wt limit of 250 kg with a WDH, however the ball weight of my rig is only about half that. I am aware that bags do not redistribute the weight (there's no physical way they can). I fitted mine to level the vehicle and save having to readjust the headlights.

codgerswa · Newbie

PeterD wrote:
Very well put Peter D, completly understood, Cheers, codgerwa.
There has been a bit in 4WD and vehicle newsgroups regarding bent chassis on single &twin cab utes. A lot have stated that air bags were in use. Others made no statement one way or the other.

When you add air bags, you are transferring the lift on the chassis from the two points at the spring eyes to a single point at the air bag. Whilst the load has not totally been transferred to the air bag lift point, it has severely changed the stresses on the chassis. The chassis will not necessarily bend above the air bag but it will bend where a newly formed (by the addition of the airbag) weak spot has ocurred.

If you want to see the difference between a leaf spring two support point suspension and a single point spring mounting, just climb under a Navara and a Pathfinder. Although there are many common items in both vehicles, the rear ends of their chassis are completely different.

-- Edited by PeterD on Friday 26th of November 2010 12:08:08 PM

jimricho · Guru

Confusion Reins confuse

...... On the very few attempts I had at riding a horse I think that's what I had in my hands!!! Or did you mean confusion rains, I think that's what the weather bureau sometimes predicts.... or perhaps...confusion reigns ? If it didn't before I bet it does now! wink