Technical Fiat/Hymer motorhome

[hymervan]

Hi,
I have a Hymer A Class motorhome based on a Fiat Ducato. I find the ride is bumpy and hard on all but the flatest of roads (and there aren't many of them around), and am thinking of fitting air bag suspension on the rear axle to help with absorbing some of the jolting.
Has anyone else had the same problem and found the addition of air suspension to have helped?
Cheers,
Peter

 

[T14086]

Please supply full vehicle details

 

[PeterM]

I find the ride is bumpy and hard on all but the flatest of roads (and there aren't many of them around)

As T14086 has said, more details please. Have you checked whether the rear axle is hard up against the stopper cones? That would give a very hard ride and may be due to the motorhome being overweight. So that also leads me to ask have you checked the axle loading on a weighbridge? Curing the cause is more important than trying to deal with the symptoms!

 

[hymervan]

Hi,
Thanks for responding to my query re. air bags on my Hymer van.
The vehicle is a 1999 A Class motorhome on a Ducato chassis and a Fiat 2800cc turbo diesel. Max. laden weight is 3500kg, but on visiting a weighbridge reasonably loaded, the front axle registered 1685kg and the rear 1510kg. I had 4 new tyres fitted December and I contacted the manufacturer, Avon, to get recommended tyre pressures based on the above weights. They came in at 51psi on the front and 46psi on the rear.
We travel quite light on holiday and the bump stops are a couple of cm. above the leaf springs when the van is stationary, but maybe the stops and springs make contact going over rough roads!
I hope this is enough information for you.
Cheers,
Peter

 

[PeterM]

Recommended tyre pressures are low. Would give a too-soft ride with instability? Weights look OK, but only a couple of cm clearance to bump stops does seem very small. Those springs flex a lot.

Try using higher pressures in the rear - up to 65 psi depending on what the placard on the door pillar says. Harsh ride but maybe not so much spring movement.

Air bags would be one way of dealing with that. There are two guides on the Forum dealing with fitting air bags to the Ducato - would give you an idea of what is required. See https://www.fiatforum.com/miscellaneous-guides/.

 

[John C S]

Agree with PeterM. far too low on the pressures.

On the Maxi Van 3.5T running 215/70/R16's, recommended is 68.6 psi on the rear tyres.

 

[bryan]

Hi There If you look on Motor Home Facts website you can also look on there tech dept this site has over 46,000members so there is a lot of information on all fiat based motor homes Hope this is also a help to those of you that don't know about the site

 

[Peebees]

Good morning, I'm very new to this forum thingy...but would like to know if hymerman had air suspension fitted in the end. We think we would like it on our 2003 hymer. can't do it our selves and would like to know who to approach about having it done. all advice greatfully received thanks

 

[Peter James]

the front axle registered 1685kg and the rear 1510kg. I had 4 new tyres fitted December and I contacted the manufacturer, Avon, to get recommended tyre pressures based on the above weights. They came in at 51psi on the front and 46psi on the rear.

Thats about what I was quoted by Michelin, and slightly more than the tyresafe chart so I'm sure its enough. Van handbooks quote more because whitevanman is hardly likely to weigh his van and adjust pressures for each load. More likely to forget to check them and overload his van. So they quote a higher pressure to allow for this.