Air suspension

[Barcobird]

I have a Pilote 741G, A class, fiat based on an alko chassis uprated to 4400 kgs with scooter rack. It has become apparent that due to the overhang in certain situations it is grounding. This had led me to two solutions, air bag or skid wheels.

 

Apparently skid wheels can have a tendency of distorting the chassis/bodywork if worked too hard.

Air bags seem the obvious choice as confirmed by other threads on this forum, however after reading the Dunlop webpage

 

"A-Class / Alko Chassis? Sorry no. Problems with Alko usually lie in the suspension itself and adding airbags will not solve it, may even make it worse. This is a professional, specialist supply & fit task not DIY. This often applies to A-class motorhomes so you will need to find out quite a bit about your A-class spec."

 

I am now confused and uncertain.

 

Does anyone have a similar vehicle to mine that has had air bags/suspension fitted to the rear only of their Motorhome and if so who did you use and what was your general impression?

[Brian Kirby]

AFAIK, only AlKo agents can carry out the work to add, or convert, the AlKo torsion bar rear suspension for air assistance or full air suspension. Why not contact AlKo UK and talk to them about the implications? If you take the AlKo chassis number from their plate, they may be able to tell you its history and suitability for adaptation to air assistance.

 

Do you know who uprated the chassis on your van, and whose scooter rack was added? My understanding is that any work to upgrade the capacity of the AlKo chassis would also need to be executed via their agents, using their products, and I would have thought would have required the complete rear axle and suspension to be replaced. This would have been an expensive operation.

 

Third party intervention without AlKo authorisation could, due to the design, result in accelerated wear of the rear swing arm bushes or stress failures of the torsion bars, or the chassis itself, possibly in the area where the Fiat stub chassis is bolted to the AlKo element. The AlKo chassis is a relative light item that is purpose made for motorhomes etc, and, where additional loadbearing capacity is required, it is usual to specify that at the time the vehicle is ordered, not to subsequently upgrade it. Apologies if I've misunderstood your post, but if the van were mine, I think I'd be initiating a few checks.

 

In direct response to your query, I would seek AlKo advice on the use of rear skids, as I suspect they would advise against for exactly the reason you cite.

[Barcobird]

Brian Kirby - 2017-05-31 11:19 PM

 

AFAIK, only AlKo agents can carry out the work to add, or convert, the AlKo torsion bar rear suspension for air assistance or full air suspension. Why not contact AlKo UK and talk to them about the implications? If you take the AlKo chassis number from their plate, they may be able to tell you its history and suitability for adaptation to air assistance.

 

Do you know who uprated the chassis on your van, and whose scooter rack was added? My understanding is that any work to upgrade the capacity of the AlKo chassis would also need to be executed via their agents, using their products, and I would have thought would have required the complete rear axle and suspension to be replaced. This would have been an expensive operation.

 

Third party intervention without AlKo authorisation could, due to the design, result in accelerated wear of the rear swing arm bushes or stress failures of the torsion bars, or the chassis itself, possibly in the area where the Fiat stub chassis is bolted to the AlKo element. The AlKo chassis is a relative light item that is purpose made for motorhomes etc, and, where additional loadbearing capacity is required, it is usual to specify that at the time the vehicle is ordered, not to subsequently upgrade it. Apologies if I've misunderstood your post, but if the van were mine, I think I'd be initiating a few checks.

 

In direct response to your query, I would seek AlKo advice on the use of rear skids, as I suspect they would advise against for exactly the reason you cite.

 

Hi Brian,it's 3 months old and apart from scooter rack came out of pilotes factory as ordered and described.

[Brock]

When I added semi air suspension to my A-Class motorhome in 2013, only three firms made a system for the Alko chassis - AS Air Suspension, VB Air Suspension and Goldschmitt.

 

I had it done to improve ride quality rather than to stop grounding although I have used it on rare occasions to raise the rear to level the van on uneven pitches instead of using chocks.

 

According to Alko, "the flexibility of the AMC chassis conversion offers a unique platform for the motorhome manufacturers to build upon, and with a full range of complementary products such as seat belt frames, air suspension systems and tow bar solutions, provides an unparalleled solution to manufacturers and end users."

 

I'd follow Brian's advice and speak to AlKo. I'd also speak to at least the first two firms I mention. Goldschmitt is now owned by Hymer and is fitted to my Hymer [it works OK for me]; I'm not sure whether it would be suitable for a Pilote.

 

Air suspension does add weight.

[Derek Uzzell]

Brian Kirby - 2017-05-31 11:19 PM

 

...Do you know who uprated the chassis on your van...

 

 

Barcobird’s Pilote motorhome’s chassis is not ‘uprated’ as such. It’s just that the Galaxy 741 model he owns could be built on a Fiat Ducato ‘light’ AL-KO chassis or a ‘heavy’ AL-KO chassis and, if the latter option were chosen, the motorhome’s maximum overall weight (GVW, MAM, MTPLM, etc.) would be 4400kg.

 

AL-KO offers “Air Plus” - a manually-adjustable ‘air-bellows’ system for the rear axle of an AMC chassis; the “Air Premium X2” system that’s automated, and “Air Premium X4” that adds air-suspension to the front axle too. The systems can be retro-fitted (but not DIY-ed) and their cost increases with their complexity. None are cheap.

[Brian Kirby]

Derek Uzzell - 2017-06-01 8:37 AM

 

Brian Kirby - 2017-05-31 11:19 PM

 

...Do you know who uprated the chassis on your van...

 

 

Barcobird’s Pilote motorhome’s chassis is not ‘uprated’ as such. It’s just that the Galaxy 741 model he owns could be built on a Fiat Ducato ‘light’ AL-KO chassis or a ‘heavy’ AL-KO chassis and, if the latter option were chosen, the motorhome’s maximum overall weight (GVW, MAM, MTPLM, etc.) would be 4400kg.

 

AL-KO offers “Air Plus” - a manually-adjustable ‘air-bellows’ system for the rear axle of an AMC chassis; the “Air Premium X2” system that’s automated, and “Air Premium X4” that adds air-suspension to the front axle too. The systems can be retro-fitted (but not DIY-ed) and their cost increases with their complexity. None are cheap.

Yep, thanks Derek, as barcobird has now clarified above, including the scooter rack.

 

My next suggestion is for barcobird to fully load the van, with scooter (but is it within the rack weight limit?) and Uncle Tom Cobley and all on board, and take it to a weighbridge and check that it is not overloaded on the rear axle, before contemplating enhancing the rear suspension. Only when satisfied that all is within limits would it be worth contemplating the addition of air assistance at the rear since, as you correctly say, it is likely to be quite expensive.

 

As this is a new van, I would also be very cautious about adding third party enhancements (edit to add, including that scooter rack which it appears may not be an AlKo item) to the AlKo chassis, with particular regard to AlKo's warranty - but also to any warranty offered by the third party supplier should some chassis related problem arise and AlKo refuse to accept liability on the basis of an unauthorised intervention. (I would also quiz AlKo closely on exactly on what their warranty would cover should their own equipment be fitted, particularly as that scooter rack has been fitted.)

 

The rear axle and rear chassis extensions are being asked to work much harder than would be the case in the absence of the scooter rack (there is also a transfer of weight from the front axle to the rear axle due to leverage), and barcobird's mention of grounding after so little time is somewhat worrying for my fertile imagination! :-D

[Barcobird]

I suggested to the dealer about taking it to a weighbridge when I collected it and he said it was not necessary because the heavier chassis gave me a payload of around a 1000kgs. They also organized the scooter rack and it was fitted before this conversation.

[Barcobird]

Also I should clarify, there is no grounding to the motorhome but only on the rear edge of the scooter rack and only on pretty steep inclines

[Robbo]

As far as I know the maximum rear axle load on a heavy Al-Ko chassis is 2400Kg (single rear axle).

 

I carry a 130Kg scooter in the garage, 1m behind the rear axle and come close to the permissible rear axle load on a heavy chassis (this includes full fresh water tank and full touring kit).

 

A scooter hung 2.5m behind the rear axle will increase the load on the rear axle and decrease the load on the front axle by a similar amount. Perhaps this is contributing to the OP's problems of grounding in occasional circumstances.

 

 

[Brian Kirby]

Barcobird - 2017-06-01 7:17 PM

 

I suggested to the dealer about taking it to a weighbridge when I collected it and he said it was not necessary because the heavier chassis gave me a payload of around a 1000kgs. They also organized the scooter rack and it was fitted before this conversation.

The dealer's advice ignores the rear axle load limit. Don't forget you have three legal load limits, front axle, rear axle, and the total for the whole van. He was addressing only the latter. The other two are at least as important and, with a scooter on that rack (which will also have its own load limit plated onto it) there is considerable scope for exceeding the rear axle limit. Very complacent advice, IMO, especially as they fitted the rack. Were you to be weighed and found overloaded, it is unlikely that quoting the dealer's advice to you would carry much weight (sorry! :-)). It is the driver's responsibility alone to ensure the vehicle weights are within their legal limits.

 

Regarding the scooter rack, are you sure it is an AlKo approved fitting, and doesn't affect AlKo's warranty? I really think you should at least look at the plate on the rack for its maker's name and, if unsure, clarify its status directly with AlKo - especially if the make is not AlKo. I have spoken to the UK end a couple of times, and found them very helpful and informative. Then you can move onto the grounding problem, and the best way to get around that without voiding their warranty.

[Barcobird]

Regarding the scooter rack, are you sure it is an AlKo approved fitting, and doesn't affect AlKo's warranty? I really think you should at least look at the plate on the rack for its maker's name and, if unsure, clarify its status directly with AlKo - especially if the make is not AlKo. I have spoken to the UK end a couple of times, and found them very helpful and informative. Then you can move onto the grounding problem, and the best way to get around that without voiding their warranty.

 

As with all things in life Brian if you are not professed in something despite forums,googling and talking to your mates down the pub, you have to be guided by the professionals, the dealers that's why you pay top dollar. I ordered this motorhome, explained what I wanted and left them to it. I am assuming (rightly or wrongly) that everything they do is within the limits of the manufacturers warranty and in no way would void the warranty with either Fiat, Pilote or Alko. I do know the company that fitted the rack and it wasn't Alko but may well be approved by them. If as you suggest there may be a warranty problem in the future then I will be going for the supplying dealer.

As you suggest I could talk direct to Alko but could be opening up a can of worms!

[Derek Uzzell]

Barcobird - 2017-06-01 7:20 PM

 

Also I should clarify, there is no grounding to the motorhome but only on the rear edge of the scooter rack and only on pretty steep inclines

 

Having looked closely at the photo of your motorhome that’s on your postings, it’s easily predictable that the combination of the vehicle’s far-from-short rear overhang, the low positioning of the scooter rack and the weight that the loaded rack will place on the rear suspension, will result in the rack grounding on steep inclines.

 

Skid-wheels MIGHT help, as the rear of the chassis might then contact the ground before the rear of the scooter-rack did, but I wouldn’t bet on it. It’s a cheapish ‘ploy’ though.

 

If you want to prevent the rack grounding you’ll either need to be able to raise the motorhome’s rear end when a steep incline is encountered (which would involve adding ‘air suspension’ to the rear axle) or (assuming that the rear chassis currently never grounds) reposition the scooter-rack so that its rear edge is higher from the ground.

[Mike88]

The problem with skid wheels is that they place undue upward pressure on the rack when contact is made with the ground.

[Derek Uzzell]

'Skid wheels’ (photos on following link)

 

https://www.wohnmobilforum.de/w-t91492.html

 

are marketed (by Sawiko) to be bolted to the lower rear part of a motorhome’s chassis and I had assumed that this was what barcobird was considering as a possible option.

 

I’ve never seen them fitted to a rear rack and (although I suppose the principle is not unreasonable) as adding wheels to a rack would further decrease the ground-clearance below it, the upwards force when the wheels contacted the ground would (as Mike says) consequently increase.

[Barcobird]

Mike88 - 2017-06-02 10:13 AM

 

The problem with skid wheels is that they place undue upward pressure on the rack when contact is made with the ground.

The rack is already getting undue upward pressure and on several occasions slightly bent the rear edge. Skid wheels would only reduce the height by 1 cm at most and it would be better for a wheel to catch the ground rather than the rack.

My first concern with skid wheels were the ones fitted to the chassis further forward which are big and solid and they may do damage but I can't see smaller ones fitted to the rack itself would cause any problems ?? *-)

[Barcobird]

I’ve never seen them fitted to a rear rack and (although I suppose the principle is not unreasonable) as adding wheels to a rack would further decrease the ground-clearance below it, the upwards force when the wheels contacted the ground would (as Mike says) consequently increase.

 

But it would be better for wheels to scrape the floor than the rack (lol)

[Keithl]

Barcobird - 2017-06-02 11:59 AM

 

But it would be better for wheels to scrape the floor than the rack (lol)

 

But these wheels would then carry the full weight of the rear of your MH!

 

Would you jack your MH under the scooter rack? I seriously doubt it would stand it so IMO the same applies to adding wheels.

 

In my opinion you either need to lift the MH at the rear axle or raise the scooter rack so it is not the lowest point.

 

Keith.

[Derek Uzzell]

For what it’s worth, the scooter-rack grounding risk has been discussed here before

 

http://forums.outandaboutlive.co.uk/forums/Motorhomes/Motorhome-Matters/Motorhomes-with-scooters/29761/31/

[monique.hubrechtsgm]

I am really impressed by the above comments. When a alko chassis cab or chassis cowl leaves their assembly plant in case of a fiat the paperwork uses the ZFA fiat code in second stage apart from the markings on the axle. In their coc is mentioned what you can add on the back, being alko products. They have an extensive instructional manual for the stage three builders being your your Rapido and all the wishes and options rapido ordered to fit their floor. Stay original on alko options, it is a leight- weight but they flex and are easely repaired by their bolt on system. They represent it as a non welding chassis, but that is not true some bolt connections have reinforced spot welding.in case of air suspension having a alko chassis go for alko. Please advice that alko uk can do a retofit. If you order new you will get a grease free alko axle if you order ALC-X2-X4. ALCand X2 is on the rear. Be aware That in case Of ALC The leveling controller you can not retrofit anymore. In case of twin axles on the rear x2 is mandatory in australia of loadsharing. Vb air suspension holds all patents of alko air x2-x4. but Vb can not retrofit on alko high frame being a rarity compared to the low frame but has 22 cm up ground clearance on the frame, but the axle itself is at the height as the standard low frame. In case of air your bellows in riding postion are very low but are in axle region. Just above tyre but steel protected in their sole.Dunlop has more alko air experience than alko itself. an alko airbag on the rear can lift you up 5cm in driving it can safe your rear bumper and waste tank. Be very carefully whit a long overhang on a low frame alko chassis.

[monique.hubrechtsgm]

In case you for for Alko X4 in rerrofit the flwg matreial will be removed from your rapido, Two Mc- pherson front struts, handbrake cable, four torsion bars, and two swing arms. you can take this material to home if you like. Two weaker torsion bars will be added to the original one left adding to 90 percent air load at bump stop They are their to keep your wheel to the axle. The compressor box will be fixed to the brackets of your fiat fuel tank. New is the Vb active Air shock absorber. Before you invest do a testdrive.

[Barcobird]

thank you Monique, I will take your comments on board and digest them *-)

[Derek Uzzell]

monique.hubrechts@gm - 2017-06-02 4:21 PM

 

In case you for for Alko X4 in rerrofit the flwg matreial will be removed from your rapido....

 

Barcobird’s motorhome is a Pilote Galaxy 741.

 

The July 2016 issue of “Camping-Car Magazine” contained an article comparing three Carthago Chic C-line I 4.2 motorhomes fitted with AL-KO’s ACS/ALC (evidently no longer retrofittable), “Air Plus” or “Air Premium x4” suspension systems, using experienced motorcaravanners as the testers. The quoted cost of retrofitting “Air Plus” was €4580 and involved two days in the workshop, while the cost of “Air Premium x4” was given as €8690 with three workshop-days. Interestingly, there was no consensus among the testers as to which system was ‘best’.

 

This link carries images of motorhome scooter-racks

 

http://tinyurl.com/ycqmuasv

 

and some of them are mounted startlingly low with a high risk of grounding. The rack on Barcobird’s Pilote is not that low (see attached photo) and it’s the long rear overhang that’s causing the occasional problem. The logical approach would be to raise the rack a few centimetres rather than spend a lot of money on modifying the vehicle’s suspension.

 

I haven’t been able to find any indication on-line that people have fitted skid-wheels to motorhome rear-racks, though I did come across a UK advert for skid-wheels intended for mounting on the chassis.

 

https://www.roadpro.co.uk/product/03k-bike-racks-and-carriers/skid-wheels-set-of-two-j6259/J6259

 

The skid-wheel principle is fine, but raising the rack would be better.

[Barcobird]

My thoughts exactly Derek, so it was sent back to the fitters who without fuss made two new brackets with a different angle and this raised the rack by about 10 cms!

I was hoping that would solve the problem which it did to a great extent but I still have the occasional problem which is mainly in the area of the red part of the reflective tape. (As seen in the picture)

[Barcobird]

Thats better we can see the photo now.

 

As mentioned generally the problem lies with the rear lip where the two reflective tapes are. I guess I could shave a bit off the bottom but I dont want to reduce the strength in any way, or I could attach small skids (castor wheels) which would stop it scraping. I dont beleive this would be a problem to the chassis, it would bend the skid wheel or the place where it was attached in the case of a heavier impact. ;-)

[Brian Kirby]

Keithl - 2017-06-02 12:28 PM

 

Barcobird - 2017-06-02 11:59 AM

 

But it would be better for wheels to scrape the floor than the rack (lol)

 

But these wheels would then carry the full weight of the rear of your MH!

 

Would you jack your MH under the scooter rack? I seriously doubt it would stand it so IMO the same applies to adding wheels.

 

In my opinion you either need to lift the MH at the rear axle or raise the scooter rack so it is not the lowest point.

 

Keith.

I wholly agree Keith. This is a large, heavy, motorhome and the idea of uncontrollable forces acting in a way unforeseen by the design of the chassis or rack would cause me considerable concern. However, it seems barcobird is content with what his dealer has fitted, and is content to pursue the dealer for remedy should circumstances demand.

 

Personally, I would far sooner confront the potential problem now, before any damage results, and resolve whether the dealer's actions may have voided warranties I might need to fall back upon: for example should the dealer cease trading leaving me with no alternative legal recourse. But that is me.

 

The obvious problem is that one can never be 100% certain what roads one may be unexpectedly directed down when travelling (diversions etc.), so can never be certain that measures such as skids or wheels will be up to the job when the cbips go down. However, the important thing is that barcobird is comfortable with the solution he has.