Suspension Troubleshooting suspension - with audio
#1
07-27-2017, 02:52 PM
Troubleshooting suspension - with audio
Hi All,
So I replaced my front stuts on my 2003 R53 with Bilstein B4's and Sachs mounts. Was not as easy as I would have thought but finally got it. Since then there is a noticeable Thunking sound that correlates to road bumps but doesn't require significant bumps etc. to cause the thunk. Also, the size of the road bump doesn't seem to accentuate the Thunking anymore than a smaller bump - it seems that if it happens at all it sounds about the same each time. There are no issues while turning the wheel or anything else. The thunking occurs while driving straight and seems to correlate to the suspension responding to the road.
I have included a series of audio files that I find pretty interesting and potentially revealing. These were recorded with a decent portable (Sony) handheld recorder using an electret condensor attached to a strong magnet. Depending on where the mic is positioned, the sound is wildly different. Most pronounced is what can be heard in the strut mount recording but do note that the mic was particularly close to the mount (2"). Also, these recordings are not all done simultaneously but used the exact same route (a relatively mellow urban neighborhood with average pavement anomalies).
Would love to hear opinions from the gallery as to what the problem is.
Thanks in advance for listening and then chiming in
Jack
So I replaced my front stuts on my 2003 R53 with Bilstein B4's and Sachs mounts. Was not as easy as I would have thought but finally got it. Since then there is a noticeable Thunking sound that correlates to road bumps but doesn't require significant bumps etc. to cause the thunk. Also, the size of the road bump doesn't seem to accentuate the Thunking anymore than a smaller bump - it seems that if it happens at all it sounds about the same each time. There are no issues while turning the wheel or anything else. The thunking occurs while driving straight and seems to correlate to the suspension responding to the road.
I have included a series of audio files that I find pretty interesting and potentially revealing. These were recorded with a decent portable (Sony) handheld recorder using an electret condensor attached to a strong magnet. Depending on where the mic is positioned, the sound is wildly different. Most pronounced is what can be heard in the strut mount recording but do note that the mic was particularly close to the mount (2"). Also, these recordings are not all done simultaneously but used the exact same route (a relatively mellow urban neighborhood with average pavement anomalies).
Would love to hear opinions from the gallery as to what the problem is.
Thanks in advance for listening and then chiming in
Jack
#2
07-27-2017, 11:29 PM
Moderator
1) moved you to Gen1 Suspension forum where you'll hopefully get the best advice.
2) check the swaybar endlinks, the nuts are one-time lock nuts and loosen up easily if they are re-used. Use some Loctite Blue on them and torque to spec.
3) check that the top nut on the shocks is properly torqued. I had a rattle in my other car that was driving me nuts, I threw parts at it until I finally figured out that the shop that had replaced the front struts hadn't properly tightened the top nut.
2) check the swaybar endlinks, the nuts are one-time lock nuts and loosen up easily if they are re-used. Use some Loctite Blue on them and torque to spec.
3) check that the top nut on the shocks is properly torqued. I had a rattle in my other car that was driving me nuts, I threw parts at it until I finally figured out that the shop that had replaced the front struts hadn't properly tightened the top nut.