Re: 88 735i (E32) front wobble

[kohlbren-m-d@xxxxxxx]

- ----------------------  Original Message:  ---------------------
From:    Henri Baccouche <henrib@domain.elided>

> It's not an "arbitrary mileage point".........it's based on
> 'real world observation'.
>
> The suspension will be worn out at ~125K........if you use
> the wear tolerances as your guide and not 'the driving
> experience in my pants' method. No way around it.
>
> OE struts at that mileage are very weak compared to new
> 'struts'......In a potential accident situation, you have
> lost considerable vehicle control. The above is applicable
> to the entire BMW model line........
>
> I have no axe to grind, I just think it would be better if
> people knew that after '125K miles', many mechanical components
> are worn beyond the factory wear tolerances. Whether, they
> elect to repair everything or only some parts is their
> decision.
>
> They should be informed of the facts....

I wouldn't call it an "axe to grind" -- perhaps more of a
soapbox thing.  This person wrote in with a specific problem
and your reply was the same thing you've said several times
in the recent past, which is essentially "At 125K miles replace
everything".  It just isn't that black and white and we all
may not want to spend a couple of thousand bux to deal with a
$300 problem...

I certainly agree that many suspension/drivetrain components
in a typical BMW (and many other cars...) are wear items that
typically only last half as long as the body and engine
block.  There are components that don't last even that long --
thrust arm bushings, for example.  The Boge struts that BMW
puts into most of their cars can be worn out long before 125K
miles depending on use.  But then, you should replace these
parts based upon their condition rather than some arbitrary
mileage.

With all due respect, your answer is not terribly helpful to
someone who may be merely trying to keep an old car on the
road and in reasonably safe condition without spending a
large fraction of its market value to do so.  Perhaps this
car only has 60K miles on it -- what good would your advice
do?  Perhaps this car has already had everything replaced
30K miles ago and the thrust arm bushings are simply worn
out?  This does happen -- the ones installed on my '92 535i
long before they had 125K miles on them were shot after
about 25-30K miles and are getting really bad now after
another 5-10K miles.  And by the way, the front struts were
done at that same time, none of which I would have known
without the service history I received with the car when
I bought it.  If I didn't have that knowledge and followed
your advice, I'd be wasting money on new struts soon simply
because I was reaching that magic mileage point.  Of course,
I can tell that the front struts are fine.  The rear shocks
are another story altogether...

I feel as though I gave this person some very specific advice
as to where to look for the source of the 55-60mph shimmy.
Perhaps based upon budget and priority, that is all that is
needed or wanted.

My only point is that it is perfectly acceptable to replace
suspension components based upon their actual condition and the
owner's preferences and budget rather than some arbitrary -- yes,
arbitrary -- mileage point.

Regards,
Mike Kohlbrenner

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