I posted a while back about my caravan that had a real problem with dips and
holes in the road, even though the struts had been replaced at a dealer by the
previous owner about 35,000 miles ago. It would bottom out with a very loud
thunk on even minor dips in the road.
Replacing the struts today, I discovered that whoever had replaced the struts
previously had completely left off the jounce bumpers - rubber blocks that
prevent the struts from bottoming out. The new struts with the boot kit that
included the jounce bumpers has solved the problem.
Excuse me for saying this, but your explanation does not make sense. The rubber
bumpers are supposed to engage only when the
suspension is either fully extended or compressed. You stated that this occurs
on minor road undulations. Those will not cause the
rubber bumpers to come into play unless something else far more drastic than
extension bumpers is at fault. Perhaps you meant the
rubber compliance washers were missing at the shock connection to the tower.
Since my explanation is far more likely than yours
and you were most likely paraphrasing the mechanic's explanation, you probably
didn't need new struts in the first place and could
have resolved the problem with .50 cent rubber washers. So how much did this
On Sat, 24 Apr 2010 21:05:03 +0200, "Steve Lusardi"
The man said he replaced the struts himself and found the jounce
bumpers missing. - so no, he was not paraphrasing what his mechanic
said - and if the shocks were weak, they WOULD bottom on relatively
minor road undulations - and without the jouince bumpers that WOULD
make it noisy. And they only come into play on compression - not
rebound, or as you called it, extention.
On MacPherson strur suspensions like this vehicle uses there are NO
$0.50 "compliance washers" between the shock and the shock tower.
The upper strut pivot assemblies kook after compliance between the
strut and the body and cost a whole lot more than fifty cents.
And probably, the lack of jounce bumpers destroys shocks, since they then are
the recipient of all the forces of bottoming out. (In addition to the mounts,
engine mounts, etc.)
I replaced the struts, seals, jounce bumpers and strut mounts (with a bearing -
one of which was bad on the old ones). Total cost $240 IIRC. After months of
"BAM" at every dip or pothole, it is a pleasure to drive now. With the lifetime
warrantee on all the parts, I'm covered as long as I keep the van. Probably a
The old struts had been replaced about 35,000 miles before I got it by a Dodge
dealer. If the missing jounce bumpers didn't cause the problem, I don't know
what would be more likely.
The missing jounce bumpers could allow the shocks to violently
"bottom" , damaging the shock mechanism (valving in th bottom of the
oiston). The jounce rubbers ARE there for a reason.
However, the biggest noise was LIKELY the strut mount if by "bad" you
mean the rubber was separated.
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