Air bags in the rear suspension

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Discussion

iiyama

Original Poster:

2,201 posts

208 months

Thursday 29th October 2015
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How are they used? I thought they were there to level the van up? Or are they used for beefing the rear suspension up when loaded? or both? Help obviously required!! smile

Bobhon

1,059 posts

186 months

Thursday 29th October 2015
quotequote all
Depends upon the design of the suspension system but generally the air bag takes on the function of being the spring. On Land Rover air suspension you have the air spring in each corner and a separate damper (shock absorber). So no coil or leaf spring.

Air suspension gives a smooth ride and the ability to have variable height suspension settings. Ideal for an off road vehicle where greater under body clearance is useful. Also the air springs get pressurised to level the car whatever the loading. Ideal when you're towing a caravan with a bit of nose weight.

I guess that you could get systems under Motor homes where there is a coil spring and an air spring or a leaf spring and an air spring but the air spring is still acting as part of the overall spring element.

With an active air suspension you need wheel height measurement systems, a compressor and control electronics to run the system.

HTH

Bob

BigBob

1,471 posts

232 months

Friday 30th October 2015
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IME they have multi uses on motorhomes: They can be used to 'balance' the rear droop depending on load; they can vary the ride 'quality' depending on load ie soften up the ride on motorway cruising to make a softer, more pleasant ride or stiffen the ride by reducing bodyroll on winding, twisty roads.

BB

iiyama

Original Poster:

2,201 posts

208 months

Friday 30th October 2015
quotequote all
Thanks BB.

The rear suspension is basic leaf spring and shock, (base vehicle being a Peugeot Boxer chassis cab).

The air bags are mounted between the leaf spring and the chassis, no electronics that I know of.

SimesJH

768 posts

158 months

Sunday 1st November 2015
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I have them in the rear of my 1992 Mercedes RMB motorhome.

When I first bought my RMB, the rear sagged a little and we quickly concluded the rear leaf springs were past their best. That was rectified with new uprated leaf springs, but it didn't fully address things to my liking and so I had VB rear air assist springs installed by a company in Birmingham called Conrad Anderson.

I now have the bags plus individual dash-mounted switches and gauges for each bag and a small hidden compressor on a permanent live.

I use them for stiffening the rear, adjusting for load and a small degree of levelling when on-site. Fabulous! Highly recommended.


Spuffington

1,238 posts

175 months

Tuesday 3rd November 2015
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Do you mind me asking how much that setup cost, SimesJH?

I've often thought about air-ride for our Merc Hymer.

SimesJH

768 posts

158 months

Wednesday 4th November 2015
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About £850 from memory.

That was for the rear bags, compressor, valves, in-cab controller for each bag including gauges and installation. It took them a full day with about 3 people on the job.

Conrad Anderson did an incredibly neat job and I think it was well worth the money.

It can be done as a DIY job for much less, though.

Spuffington

1,238 posts

175 months

Thursday 5th November 2015
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Thanks mate - much appreciated.

will2020

433 posts

186 months

Friday 6th November 2015
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I've a kit on my Navara for use when pulling a 5th wheel, simple instal for anyone with a bit of sense. http://www.driveriteair.com/en