Alko Air Suspension

[spartan3956]

I am thinking of fitting air ride to the rear of my motorhome to assist when towing a trailer.

I feel that the front is getting lighter and if I go off tarmac I have problems getting grip on front drive wheels.

Has anyone had this system fitted and if so who by.

Is it worth the initial cost.

 

The vehicle is Renault based with low line chassis weighing 3850 kg.

[Brian Kirby]

Have you taken your van to a weighbridge and checked the load on each axle? If not, it would be a good place to start.

 

I ask, because lack of traction is a symptom of too much weight concentrating at the rear.

 

Motorhomes share weight between the axles in much the same way that a see-saw works. The rear axle acts as the pivot, with any load added behind the rear axle removing load from the front axle.

 

If this is the case with your van, adding air assistance will not cure the lack of traction. The only way to do that will be to transfer load from the rear to the front - or at least from behind the rear axle to ahead of it. The added bonus is - it won't cost you anything! :-)

[spartan3956]

Well after exhaustive enquiries I find there isn't a kit for Renault based vehicles anyway.

The vehicle doesn't have a big over hang either. But I do carry a Honda c90 on a rear rack .

I suppose I could relocate the spare wheel make sure the trailer is loaded to reduce nose weight .

Running with full fresh water tank helps .

I'm changing the front tyres the Continental Vanco banded tread pattern I have , it doesn't help on grass or in the rain on tarmac, they just spin up .

As a last resort I could just put my Polar 16 mm snow chains on which act as a catapilar tractor. Good for digging trenches .

A limited skip diff would be nice.

 

 

 

 

[monique.hubrechtsgm]

Motor homes front wheel drive in 3850 kg going in off road condition will suffer traction and underbody

clearance problems of the tanks and drain piping. Air will keep you in the set level riding height for a particular axle. It can lift tons. But your traction problem remains. They are not made for that. In case you are off road anyway buy a good four wheel drive or take some anti slip courses.

[spartan3956]

New front tyres fitted with a better tread pattern been on grass today more grip no spinning to report.

I was concerned having a block tread they would be noisy but not the case.

Glad those Continental vancos are in the skip.

 

 

 

 

[Derek Uzzell]

Replacing 5-year old tyres should be expected to result in improved grip whatever the new tyres' tread pattern.

 

I've had Continental Vanco-8 and Vanco 2 tyres on a fwd Hobby motorhome and my present fwd Rapido has Michelin Agilis Camping M+S-marked tyres. None of these tyres would grip well on WET grass, that is worse than ice in many ways as there's often the potential to break through the top surface and bog down.

 

Unless a tyre with a very aggressive tread pattern is chosen (e.g. a tyre more suitable for a 4x4 than a motorhome) obtaining grip on wet grass will always be challenging - and if you are towing too, things will be even trickier.

 

It is also advised that, when two tyres are replaced, the new tyres are fitted to the rear wheels, and this is irrespective of whether the vehicle is fwd or rwd. Old worn tyres on the rear wheels and new tyres on the front wheels risks uncontrollable oversteer when cornering hard on slippery roads and/or in an emergency.

[Brian Kirby]

spartan3956 - 2017-09-06 5:26 AM................. But I do carry a Honda c90 on a rear rack .

I suppose I could relocate the spare wheel make sure the trailer is loaded to reduce nose weight .

Running with full fresh water tank helps ....................

Yes but! :-) The rack effectively extends the rear overhang, and the bike carried on it is placing its load well behind the rear axle. This inevitably removes load from the front wheels.

 

I'd still be inclined to fully load you van to touring trim, and take it to a weighbridge, before considering any suspension mods, since a lack of traction such as you are experiencing strongly suggests insufficient load on the front axle to drag the rear axle along when on slippery ground.

 

I note you've now changed the tyres and, as Derek says, almost any new tyre would give better grip than 5 year old Vancos. However, if the weight balance is poor, similar traction problems will be likely to arise in future, as the front tyres wear.

 

You may prove to have applied an Elastoplast to an inherent problem. Shifting weight would, I suspect, give you a permanent remedy, plus a more stable van.

[monique.hubrechtsgm]

The ultimate you can buy having a alko cchassis is a alko full air suspension all original designed by one company. You can add four alko hy4 legs and you have it all. They do not solvetraction off road. And not any FWD tyre will do. Off road in the mud put your MH on blocks on the front and the rear. And ride off them in low rev. Never grave in your traction tyres FWD.

[weldted]

Hi, just to give you an idea of costs? I have just fitted VB semi air to my 2012 Elddis Aspire 255. It was updated at purchase (new) from 3500 to 3700 I now have updated it to 3850. This involved the VB kit and new plate and dvla paperwork being carried out by SVtech. Excellent help and advice from Gareth Marsh.I fitted the kit in around two hours, with paperwork £720. Then fitted 225/75 r15 (112) tyres up from 215/75's

To bring the rear axle up to 2250 kg.

[monique.hubrechtsgm]

Looks nice done. But to understand correctly: did you have a low or high frame alko chassis, or fiat?

[Derek Uzzell]

Monique

 

Details of a 2012 Elddis Aspire 255 can be found here

 

http://www.elddis.co.uk/documents/Brochures/2012/5699-Aspire-Brochure-2011-2012-LOW-RES.pdf

 

http://www.elddis.co.uk/documents/Brochures/2012/5805-Aspire-Price-List-2012.pdf

 

The model was constructed on a Peugeot Boxer 335 3500kg long-wheelbase non-AL-KO chassis. The motorhome is quite long and this YouTube clip shows that it has a significant rear overhang.

 

 

It will also be apparent from the Elddis documentation that a 3500kg version of the Aspire 255 would have a very limited user-payload.

 

In the October 2017 issue of MMM there’s a 5-page “Levelling and air suspension” article. As the article explains ’supplementary air assistance’ (ie. a couple of air-bellows units fitted to a rear leaf-spring suspension system) can be quite inexpensive (currently as little as £279) and installation is usually straightforward.

 

The original poster (spartan3956) owns a Bentley Donnington motorhome built on a Renault Master with AL-KO chassis.

 

https://www.caravanguard.co.uk/news/bentley-donington-motorhome-reviewed-2395/

 

As Bentley ceased trading in 2012 there is no factory support for this make of motorhome nowadays, though there is an owners’ club.

 

http://www.bentleymotorhomeowners.co.uk/

 

The number of motorhomes based on a Renault/AL-KO combination will be quite small, so it’s not too surprising that no rear-suspension air-assistance ‘kit’ is marketed, though a specialist company like VB-Airsuspension might be prepared to custom fit that type of modification if the customer were prepared to pay lots of money.

 

However, despite air-assistance helping to deal with a motorhome’s inadequate rear springing, it will not produce an improvement in traction, - which is what spartan3956 was seeking to achieve.

[monique.hubrechtsgm]

The alko suspension on air up to all wheels is invented by VB, A dutch company. Alko still buy from them in some contract the components.Alko had their versions on their own axles.Both are unable to show in real detail on the internet how their system works on all versions of chassis. Alko is best and have ground approval from the start but Vb runs whit type approvals and very pricely, and not a company to communicate whit.to get it approved.

[weldted]

You are right about the 3500 version having very little payload, at the time we purchased the van new at the NEC Oct 2011 Elddis were offering a free paper up rate to 3700 vis SVtech. This still left it tight for extended touring, by the time a second battery tv's solar panels inverter and LPG tank were fitted it was always close.

So I contacted SVtech for advice I found them to be very helpful and although at nearly £900 I was able to increase max to 3850 and by fitting the larger rear tyres got the rear axle to 2250 kg important beacause as stated this van does have a large rear overhang. My post was not to suggest a Soloution to the wet grass problem only to give the original post an idea of costs in Uprating payload, if anything it may aggravate the problem as in therory more weight can be carried towards the rear of the van. We try to keep heavy items under the front bench seats but by design most of the storage it over the rear axle.

[Billggski]

As the OP was enquiringly about air suspension to help with towing a trailer, and already had a motor bike on the back, there is presumably a towbar fitted already.

So the advice to take it to a weighbridge fully loaded is sound.

I'm surprised the front wheels are still on the ground! ??

[Derek Uzzell]

weldted

 

It’s interesting that in 2011 Elddis were offering an on-paper weight increase from 3500kg to 3700kg via SVTech. Previous forum discussions have suggested that Fiat are not prepared to authorise this type of uprating (even though no mechanical modifications are involved) and, consequently, the Fiat warranty may be negatively affected. Perhaps Peugeot are less picky about such things.

 

Adding ‘air assistance’ to an AL-KO axle (as fitted to the OP’s Bentley motorhome) will be quite expensive. The parts will be dearer

 

https://www.aandeleisureshop.co.uk/vb-airsuspension-al-ko-alko-semi-air-kit.html

 

and installation will be more challenging. I don’t know if any forum member has DIY-ed this task, but I recall previous ‘professional’ labour-time estimates of six to eight hours.