Hello Doug
You will find the majority of dual axle vans that are not off road have roller rocker suspension and are quite adequate for bitumin driving with some dirt roads and free camps
Ken
There is a significant difference between "rocker suspension" and "roller rocker suspension", the first puts a lot of load on parts and needs a high level of service, the second works much better.
If I was you, I would insist on Roller Rocker suspension, then add the shockers just to make it even better.
There is a significant difference between "rocker suspension" and "roller rocker suspension", the first puts a lot of load on parts and needs a high level of service, the second works much better.
If I was you, I would insist on Roller Rocker suspension, then add the shockers just to make it even better.
I've had both and personally I much prefer full rocker which utilises proper shackles rather than a roller rattling around inside a loop at the end of the spring - the shackles are much more solid and properly locates the spring. Not sure where the "high level of maintenance" comes in as it just requires a pump of grease occasionally (just like rockers do). I do a lot of off road travel and do NOT run shockers with this type of suspension. I find the leaves are short enough to avoid any serious resonance issues over corrugations (when driven sensibly) and shockers tend to just stiffen the suspension and transfer additional shock through to the van.
I have the rocker roller suspension without shocks on our 23 Jayco and have travel 000sk with water in the kettle , toaster, bowels of fruit and the list goes on all sitting on non slip mats sitting on the bench and table and have never had any fall off. My point is that the shocks are just another thing to fail while you are traveling. However, if you tend to do a lot of off road then they are a must.
In my younger years i had a 16 foot hartley trailer sailer home build boat on a trailer fitted with torsion suspension. This towed beautifly and never gave any trouble. Also can be fitted with hydraulic disc brakes.
May not be suitable for caravans though.
Cheers Jeff
From my point of view it is essential to have load sharing suspension. If it is not any undulation will increase weight on one wheel and take off the other. I would go for the best load sharing you can afford, non load sharing is not an option.
Be wary of some well known brands of van that advertise independent suspensions, they are not all load sharing. I got caught and found the increased weight going on wheels was bending the supports. Got out of it after 11 months, actually the manufacturer decided to by back from me.
I doubt you will have any issues with the set up in above pic..
Much the same I have fitted to car trailer I use often..
It's very quiet over speed bumps even when empty ..
No need to grease too often.. Once a year depending on
Mileage , conditions ..
The rear leaf spring can be swapped to the front to give wider ( further apart) wheel spacing if required ? Shock IMO are not mandatory .. But if I had the chance I would fit them. It would help excessive movement on sharp pumps roads , metal , sandy ruts etc.. Make sure the brackets are strong!! And body where attached ..
GerryP wrote: I do a lot of off road travel and do NOT run shockers with this type of suspension. I find the leaves are short enough to avoid any serious resonance issues over corrugations (when driven sensibly) and shockers tend to just stiffen the suspension and transfer additional shock through to the van.
I tend not to agree with that statement. Read the following article:
Scroll down to The Role of Shock Absorbers that section will demonstrate why they are necessary. This was writtten by a bloke who worked for GM in England and did a lot of testing on truck suspensions. Many years ago they did not put shockers on truck "because they were not needed." I note that there are not many new trucks on the market that don't have them. The bit I like inthat article is:
"Whilst at GM, I devised a test rig that simulated bump action on damped and undamped axles. Many undamped axle assemblies loosen and/or break wheel studs. Adequately damped ones don't. I later data-logged the shock loadings on a leaf-sprung QL Bedford whilst I drove it twice across Africa. The difference in shock loading on rebound (between a damped and undamped rear spring) was on average thirty five times greater."
I have shockers on my single axle van.
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PeterD Nissan Navara D23 diesel auto, Spaceland pop-top Retired radio and electronics technician. NSW Central Coast.