A Cruisemaster XT setup with dual shock
absorbers from about three years ago.
Shock absorbers: These dampen the
oscillation of the coil springs, especially during
suspension rebound. They also control the
transient movement of the van body, such as
during a lane change.
Brakes and hubs: These are connected to the
control arms and wheels.
COIL ADVANTAGES
What are the main advantages of an
independent coil setup over any other type of
suspension system?
“Each of the suspension systems have their
applications unique to their functionality and
are used accordingly,” AL-KO’s Jibu John said.
Having said that, he pointed to the “higher
range of unparalleled articulation that suits
offroad conditions, due to the long travel and
flexible nature of coil springs”, as one of the
clear advantages of independent coils.
They also offer increased ride height and
centre ground clearance, and because coil
springs are not rigidly fixed to the chassis,
there is greater scope to adjust and customise
the suspension geometry.
Another important advantage: they free-up
space for other caravan components, such as
a water tank between the two control arms,
which is harder to achieve with a beam-axle
leaf-spring setup.
“Continuous wheel-to-ground contact and
ride comfort is largely possible using
independent coil suspension systems, due to
independent movements of suspension arms
between both sides,” Jibu said.
This, of course, is not necessarily a given with
a beam-axle setup.
Andrew Goddard added that if designed
correctly, a coil system would ride better as
the spring rate could be controlled more
accurately, with the dampening done
hydraulically in the shock absorber instead of
by inter-leaf-spring friction.
Finally, coil springs by themselves are
generally low in cost, easy to replace for a
specialist, and very durable.