Safe or not Safe

Jackie · Veteran Member

Safe or not Safe

elliemike · Guru

Jackie wrote:
What does the forum think of running 45 psi in air bags to help level up van with the use of WDH to take up the rest of the sag thus putting weight back on the front wheels, this is on a Nissan Parthfinder rated at 3 ton towing hitching up van approx 280kg on ball with van weight of 2800kg, and yes have these weights confirmed at a weigh station. Look forward to your comments.

Have you sorted the weight out in your Van it might have too much weight up front.

I think getting a new "Tow Vehicle" that can handle the load would be on the agenda. Or sort out the loading of the van if that is the issue.

What is the upper pressure recommended by the Air Bag Manufacture. When I had air bags on a vehicle I think 5 PSI ? was recommended. I went to a larger 4x4 because I was not happy with the loading on the back of my tug.

-- Edited by elliemike on Monday 22nd of February 2016 03:34:28 PM

Dav4Cris · Senior Member

From memory when I was looking at airbags for my ute, max that was recommended was 15psi, anything above was going to put extra pressure on the vehicle chassis. SO went with extra leaves in the rear springs.

Peter_n_Margaret · Guru

I suggest you need to weigh the rear axle and front axle of the tug separately, when fully loaded.
Each axle has a separate weight rating and you need to know what they are and never exceed them.
If you need air bags, you are already overloaded. They don't do any of the weight transfer of the WDH.

Cheers,
Peter

Stl · Senior Member

Hi Peter,

To level the van I would adjust your tow ball height on your WDH. If you pump the air bags over 15 psi the weight is in a central point, not letting the springs do their job, and could crack your frame, as already said 5 - 15 psi is the range too only go for to help for a smother ride not to be used as a levelling tool. As already said heavier springs are the go.

Len :)

blaze · Guru

Stl wrote:
Hi Peter,
To level the van I would adjust your tow ball height on your WDH. If you pump the air bags over 15 psi the weight is in a central point, not letting the springs do their job, and could crack your frame, as already said 5 - 15 psi is the range too only go for to help for a smother ride not to be used as a levelling tool. As already said heavier springs are the go.
Len :)

hasn't the pathfinder got coils, if there is no point of difference in contact for springs and airbags.

My old air bags had a min of psi and a max of 90 psi

cheers

blaze

elliemike · Guru

Just posted this on our Avan WA club website in relation to getting the load distributed correctly in Avans to ensure correct Ball weight for safe driving. I wonder what the root cause of this crash was.

blished on Oct 4, 2015

"This footage was taken (3/10/15) from a bus. It was loaded with party goers on the way to Randwick Races. It's the M1 Pacific Motorway NSW at Mt Colah (just north of Sydney). "
Footage thanks to Sam

-- Edited by elliemike on Monday 22nd of February 2016 03:42:55 PM

PeterD · Guru

elliemike wrote:
Have you sorted the weight out in your Van it might have too much weight up front.

I think he has sorted things OK. Unless he has a European style van then he does not want less weight on the ball.

-- Edited by PeterD on Monday 22nd of February 2016 04:28:25 PM

PeterD · Guru

Jackie wrote:
What does the forum think of running 45 psi in air bags to help level up van with the use of WDH to take up the rest of the sag thus putting weight back on the front wheels,

As said above, air bags do not restore the weight to your front wheels.

People get too hung up about levelling their rig. The whole exercise of installing WDH is to get weight back onto the front wheels. However too many attempt to get their tug looking as it was before it was loaded. This places far too much load onto the front wheels.

If you load your vehicle up and don't overload the vehicle it will naturally be down a little at the rear. The vehicle should look much the same when WDH is applied. What WDH does is to shift the effect of the loading location from the ball to just behind the rear seat. That should shift enough mass back onto the front axle for good stability in the tug. If the tug is lower in the back end with the van hitched than it would be with that 280 kg weight over the rear axle then you are overloaded. Remove weight from the rear of the vehicle, air bags are not the fix.

Jackie · Veteran Member

The recommended upper psi for my air bags is 60 psi, so not concerned with the pressure, 280kg on the ball is 10 percent of van weight which I beleive is OK, my main concern with having the air bags at this pressure was the chassis, would this create extra load on the chassis. I have always travelled with 30psi and WDH, however rear of vehicle was down a bit, so was just experimenting with getting the tow rig level and is this important. Elliemike do not need new tug, as have towed van many KM round this great country and touch wood have not had any problems.

TheHeaths · Guru

The Airbag Man airbags we have show a maximum inflation of 30 psi.

I suggest checking 1) what is maximum psi shown for your airbags? 2) What is maximum ball weight for the vehicle from the owners manual. 3) Does the van currently fit under that maximum ball weight? 4) What is the rear axle weight, and what is the maximum allowed by Nissan?

Also remember that the airbags will transfer no more weight to the front wheels.

If it is looking as though it needs to be levelled like this, I would also check the weight on the rear axle of the car with the van on, as this may be over if the unit looks like it need to be levelled, as mentioned by Peter and Margaret.

Good luck working out something.

Aus-Kiwi · Guru

If it's bottoming out on bump stops I would move weight around or add a little more pressure . I assume this pressure is with no weight and standard ride hight ? 30lb with weight is bugger all when bags lift when weight is off .. I assume they are coil Spring ? Fitting heavier springs is easy . There is not the same chassis strength issue with coil / air bag combo ..

mr glassies · Guru

You got that rite kewe imagin what 60 psi would do to a leaf Spring vehicle specially a ute . Air bagels I don't like or recommend

Dibs