rattle from suspension or something else? 1998 S90

thefisch · Post by **thefisch** » 04 Apr 2021, 19:24

For background, the front struts started leaking on our 1998 S90 about 3 months ago. Ride is bouncier and struts groan over speed bumps. We are planning to address in a few months after saving up.
viewtopic.php?f=2&t=96221&e=1

In the past few days, we started to notice a rattling sound over rougher surfaces - seems like metal on metal. While driving, it mainly occurs when the road surface gets rough or going over road pavers/bricks or little bumps in the road like manhole covers. Accelerating, braking or steering input doesn't seem to cause the rattle. And we don't hear it on smooth roads until we it a rougher patch. I recorded an audio file below.

Volvo rattle1.mov: (239.09 KiB) Downloaded 718 times

Control arm bushings, sway bar links, etc are older but all seem to be intact - not gone enough to allow metal to metal contact. Heat shielding along exhaust path is not loose either. Wonder if this could be coming from strut bearing plates. Any suggestions based on the sound?

lummert · Post by **lummert** » 05 Apr 2021, 14:06

I'm guessing lower control arm inner bushing. My 1988 760 turbo wagon has a similar issue when turning into rough driveways. Upon inspection the lower control arm inner bushing appear worn.

thefisch · Post by **thefisch** » 05 Apr 2021, 14:52

Here are some close-ups on the lower control arm bushings on the driver and passenger side. Yup, they are cracking but the rubber is still there. Perhaps they are cracked up enough to allow for contact sometimes.

: driver side (should have used flash)

: passenger side

: passenger side taken with flash

thefisch · Post by **thefisch** » 06 Apr 2021, 18:35

Played the audio for a mechanic friend today and he though the frequency of the rattle indicated the strut bearing plates. Those will be replaced when the front struts get done so will know then.