Bentley Publishers - Technical Discussions : front suspension problem ...

vaclavg

Posts: 10
Registered: 06/23/05

front suspension problem
Posted: May 4, 2009 8:37 PM

I have 2006 325 xi station wagon with run flat tires
which I own since new. No special suspension features.
The car does not take the bumps or dips in the road gently - it feels like the shocks are bottoming out and the front will fall off.
If I see the problem coming and can slow down to 30-35 mph, it goes through half way decent. But it is not always possible.
The dealer replaced 1 of the front shocks and could not see anything wrong. but this did not fix the problem.
I talked to him again and he threw his hands in despair.
did anybody experience problem like this?

autobahn

Posts: 515
Registered: 08/17/05

Re: front suspension problem
Posted: May 7, 2009 11:09 AM

in response to: vaclavg

Reply

Did you issue develop over time?
Have you tried different tire pressures, just to see if this has an impact?

BTW: the weight of the car is not supported by the shock absorbers, but the springs.
Has the ride height/springs been checked for sagging?

Personally, I do not like the idea of replacing one shock absorber, they should be replaced in pairs.

Message was edited by: autobahn

vaclavg

Posts: 10
Registered: 06/23/05

Re: front suspension problem
Posted: May 7, 2009 10:50 PM

in response to: autobahn

Reply

the car has been doing this since new.
I did not take any measurements myself, but the BMW dealer checked the suspension, found nothing wrong and ordered 1 shock which was replaced later after it arrived.
I try to keep the tire press. close to the specs (maybe a bit lower in the back, they call for 39 psig).

autobahn

Posts: 515
Registered: 08/17/05

Re: front suspension problem
Posted: May 8, 2009 9:53 PM

in response to: vaclavg

Reply

Well, I would not expect that this forum can or will solve any BMW R&D ("E-Bereich") or engineering issues.

You should have realized this problem/issue during the initial test drive or complained about it as the car was still under factory warrenty.

vaclavg

Posts: 10
Registered: 06/23/05

Re: front suspension problem
Posted: May 11, 2009 9:38 AM

in response to: autobahn

Reply

the car is still under factory warranty, but the dealer says they do not know how to solve it
sounds strange

autobahn

Posts: 515
Registered: 08/17/05

Re: front suspension problem
Posted: May 11, 2009 3:30 PM

in response to: vaclavg

Reply

I don't know where you reside, but here in the US (I believe in most states), the dealer has three attempts to repair an issue, than the car manufacturer might end up taking the car back (lemon law).

soheil2

Posts: 17
Registered: 09/20/05

Re: front suspension problem
Posted: May 11, 2009 4:48 PM

in response to: vaclavg

Reply

The run-flat tires are hard. They have no give. It's likely to be just that and nothing else--though by now, after 3 years of running on those it's possible that the body of the vehicle has taken enough pounding to have loosened up and flex noisily and annoyingly on bumps.

To satisfy yourself that the shock absorbers are good (or perhaps not good), try bouncing the car when it is standing still. You should get several inches of bounce out of each corner of the car (but no oscillations).

dontpanic

Posts: 1
Registered: 09/14/09

Re: front suspension problem
Posted: Sep 14, 2009 4:34 PM

in response to: vaclavg

Reply

Vaclavq - I have the EXACT same problem, only my car has the sport package, so there are some suspension mods, even thought they're factory. Did you ever get anywhere with it?

I am very curious to know what tires you have on the car. I have Bridgestone Turanzas. They are very poorly rated on tirerack.com. They got a 2.7 out of 10. I wonder if it is mainly the tires, and not all of these cars got that model, so they don't all exhibit the issue.

I've hit potholes that have bounced drinks out of the cupholders. I hit one with the right-side tires that blistered both tires and bent both wheels. $795 to repair that mess.

Anyway, the tires are showing cords now, so I have some continental contiprocontact SSR's on order now. tirerack.com rates them at an 8, so I'm hoping this will fix things.

vaclavg

Posts: 10
Registered: 06/23/05

Re: front suspension problem
Posted: Nov 15, 2009 8:36 AM

in response to: dontpanic

Reply

I have been using continental tires - second set.
new tires did not make any difference as far as my problem goes.
I think the problem is caused by the combination of stiffer suspension and run flat tires.
the problem has been there from day one, so I do not think it is the wear or shocks.
as a matter of fact dealer changed shacks early in the attempt to eliminate the problem.

Tealeaf

Posts: 1
Registered: 11/21/09

Re: front suspension problem
Posted: Nov 21, 2009 4:08 PM

in response to: dontpanic

Reply

Brigestone Turanzas!!

These tires are absolute rubbish.
The combination of compound, design and BMW suspension
creates cupping from the shocks and inside wear from the Camber.
They wear out in 30k or less.
BMW had a program to replace up to 15k upon complaint or pay half up to 30k.
You get horrible road noise from the wear.

If you replacements ,get the Contis with tread warranty.
Don't let BMW foist you off with the same sub-par Bridgestones for this application.