How to figure out where front suspension noise comes from
#1
How to figure out where front suspension noise comes from
I have a "clanging" sound (like a metallic bang) in the front, mostly on decompression. Sometimes a knock on compression too. I.e. when I drive over a speed bump, it may knock when compressing, but definitely "clang" when wheels drop back to the ground.
I've read about anything and everything from bushings to subframe bolts. How do I figure out what is causing this?Any help welcome!
I've read about anything and everything from bushings to subframe bolts. How do I figure out what is causing this?Any help welcome!
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chassis (05-27-2021)
#3
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I have a "clanging" sound (like a metallic bang) in the front, mostly on decompression. Sometimes a knock on compression too. I.e. when I drive over a speed bump, it may knock when compressing, but definitely "clang" when wheels drop back to the ground.
I've read about anything and everything from bushings to subframe bolts. How do I figure out what is causing this?Any help welcome!
I've read about anything and everything from bushings to subframe bolts. How do I figure out what is causing this?Any help welcome!
- which end of the vehicle, front or back?
- which side of the vehicle, left or right?
- noise present on braking/deceleration?
- noise present on acceleration?
- noise present when changing lanes aggressively at speed?
- noise present on potholes?
- noise present on speed bumps?
- noise present when entering or exiting a sloped driveway?
- noise present when wheel is turned, or when straight?
Do all of the above diagnostic tests and report back.
Candidates:
- shock mount
- stabilizer link
- stabilizer bushing
- tie rod joint
- upper or lower ball joint
- brake dust shield
#4
Ok. So we lifted it up and did some digging. This is in the front, and although I initially thought it was both sides, I'm leaning towards front right now. Happens on suspension compression/decompression. There's a "knock" on compression and a "clang" on decompression.
What we tried (on both sides):
- crowbar in subframe mount bushings: no play detected
- ball joints: no play detected
- tie rods OK
- brake shield seemed OK
- upper mount seemed fine too, no play
Fundamentally, we were not able to find anything that had any play with the car hanging off a lift (we stuck the crowbar into various places, and wiggled wheels looking for play in the steering / bushings / etc).
Should I start thinking it's the shock itself that needs replacing?
What we tried (on both sides):
- crowbar in subframe mount bushings: no play detected
- ball joints: no play detected
- tie rods OK
- brake shield seemed OK
- upper mount seemed fine too, no play
Fundamentally, we were not able to find anything that had any play with the car hanging off a lift (we stuck the crowbar into various places, and wiggled wheels looking for play in the steering / bushings / etc).
Should I start thinking it's the shock itself that needs replacing?
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chassis (05-28-2021)
#5
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The road/street is the best place to do the diagnosis. Levering components on a lift will only find the most egregious component failures. Most of these type of failures are more subtle and less obvious to diagnose.
You said “compression/decompression”. Which is it? The correct terms are jounce and rebound. Does the suspension make noise in jounce? Or rebound? At fast wheel speed or at slow wheel speed?
One sided noise suggests:
- shock mount
- stabilizer bar link
- stabilizer bar bushing
- brake dust shield
- loose component (wire, hose) in the area where the sound comes from
Do the list of tests on the road and note vehicle speed when doing them. Please report back.
You said “compression/decompression”. Which is it? The correct terms are jounce and rebound. Does the suspension make noise in jounce? Or rebound? At fast wheel speed or at slow wheel speed?
One sided noise suggests:
- shock mount
- stabilizer bar link
- stabilizer bar bushing
- brake dust shield
- loose component (wire, hose) in the area where the sound comes from
Do the list of tests on the road and note vehicle speed when doing them. Please report back.