Lowered bus

[Ivorblueun]

I seem to recall someone on here saying if you drop more than 40mm its best to change the shocks else they bottom out, no doubt someone will come along with the difintive answere.

[Anonymous]

Have you shortened the bump stops?
If not you may find its either sat on them or hitting them very quickly.
I did this on my Panel van a while back and never bottomed out the shocks, even on harsh braking etc. I think I removed 2 rubber rings from the front bump stops.
At the rear I cut the metal tubes and shortened them and welded them back on.
MG

[hanloncole]

Never understand why folks do this? but then thats what makes life such an exciting and colourful thing!

[Grun]

Hi busdriver,
As nobody has yet replied to your question, I have had a look in Haynes, (too wet to venture out to the garage) and it looks to me as if the front bump stops are called 'Rubber Spring and Protective Sleeve' by Haynes, and are fitted over the upper part of the dampers (shock absorbers) inside the coil springs and below the wishbones.
Somebody with more knowledge will be along to correct me if I am wrong.
It is an area of the van that I have not yet had to work on!
Grun

[Blingpanzer]

CHANGE THE DAMPERS!

I posted this on the old forum, but here goes again:

Dampers are designed and matched to work with the normal range of operation of the associated springs. They're designed to offer low resistance for a short range around their 'nominal' position (to absorb small-amplitude inputs and cushion the bodywork to provide a good ride over average road surfaces). They're designed to be progressively stiffer in bump, to resist large wheel movement, and to enable the spring to return the wheel to its nominal position as quickly as possible to keep the tyre in contact with the road.

When installing 60mm shorter springs, you've moved the dampers 60mm into the stiffer 'bump' region. Ergo much stiffer dampers, and the nibbling ride quality you've already experienced. Dampers work via fluid friction, so by effectively stiffening your dampers, you've increased friction and hence heat generation. Wear will be rapid (the seals are not designed to cope) and life will be short.

Unfortunately, even if you could live with the ride quality, you've probably stiffened them too much, i.e. moved them way outside their designed operating range... so they'll be bottoming-out, or coming very close to it. Ergo even faster wear rate. The bounciness can also lead to the tyre being airborne more frequently, with a corresponding detrimental effect on braking distances and wet-road grip. Which you won't prove until it's too late.

Get some shortened dampers. Preferably ones which are matched to the characteristics of the springs you've bought! Particularly if you carry family or friends in your van. The suspension companies don't spend millions on R & D and damper-matching exercises for nothing.