Ever mysterious clunking noise

[rix617]

Guys I've read all the posts about people's random clunking noises and I haven't figured out what mine is yet. Everything I can think it could possibly be has been replaced in the last 10k miles. Sway bar end links, tie rods, LCAs, FCABs, steering coupler, they're all new. I even checked the end links today to make sure they're tight and it didn't have any effect. I've tried listening to the sound from inside the engine bay but I can't pinpoint it. If I lift any wheels off the ground it goes away so its impossible to get underneath to try and find it.

The only thing I can find is this post from 9 years ago; https://www.e46fanatics.com/threads/steering-clunk-yes-another-one-update-solved.1015186/
This guy described the exact same symptoms I have and ended up saying it was the "steering rack bolt bushings" had oil on them and he just had to clean them. I have no clue part he is referring to, anyone have suggestions or other opinions?

[zhaireszhp]

can you explain further when the clunk occurs? and if it has any other associated symptoms/noises? given, the maintenance you’ve performed assuming it comes from the front of the car.

[sillieidiot]

Same question. I feel like since you've heard it for so long, you can be very specific about when it happens which would help us to try to narrow it down more.

only when turning? or have to be moving? only forward? or reverse? etc.

other possible causes could be from broken springs, or maybe the bearings on the top hats being bad.

[Oli77]

So this is what the guy says over at the other forum you reference OP:

"Solved!!!! Steering rack bolts bushings where slipping. I had the oil leak from the filter to the block like everyone. oil had gotten between the bushings and mounting surfaces causing it to slip just enough to feel and just a TINY bit of movement...even though the bolts where tight. pulled the bolts, cleaned the surfaces, reassembled...no noise....SO happy!!!!! FINALLY!!!"

The noise was apparently when turning the wheel left right low speed, not going over bumps or anything.
In his case his rack was moving? because of oil from the OFHG? even though the bolts were tight?

Not sure I compute.

Yep, maybe describe your issues further Rix617.

[rix617]

Yea basically I can be sitting not moving, car off, and turn the wheel left or right and I will hear a single “clunk/pop” sound each time I change direction and cross the center. It also happens when moving at speeds below 5mph. I’ve listened for the noise, definitely from the front of the car. I’ve tried listening next to both wheels and from above the engine bay and it’s hard to pinpoint but seems like near the center somewhere.

The way the guy on e46fanatics described his symptoms exactly matched mine but as Oli77 mentioned, I can not make any sense of his response to how he fixed it.

[zhaireszhp]

does he mean steering rack coupler? i’m not aware of any steering rack bushings, or maybe he means the covers at the point where the tire rods connect to the steering rack? just thinking out loud, but since you’ve more or less changed all the front suspension bits any chance that the noise/vibration is originating from the wheel assembly, brakes/hubs/bearings etc. and the vibration is being sent through steering rack/tire rods, making the clunk. on an e39 i had, my flywheel was toast and thought i needed to replace something in rear suspension/drive shaft b/c of the vibration was reverberating through my driveline and made me think the failure point was further back than it was.

[Will]

Perhaps the strut mount / axial bearing failed?

[YoitsTmac]

Yea basically I can be sitting not moving, car off, and turn the wheel left or right and I will hear a single “clunk/pop” sound each time I change direction and cross the center. It also happens when moving at speeds below 5mph. I’ve listened for the noise, definitely from the front of the car. I’ve tried listening next to both wheels and from above the engine bay and it’s hard to pinpoint but seems like near the center somewhere.

The way the guy on e46fanatics described his symptoms exactly matched mine but as Oli77 mentioned, I can not make any sense of his response to how he fixed it.

With the car off at a stop, I've had this on basically every E46 I've owned. My buddy loves to blame the steering rack itself. To be honest, I'm not convinced and it rarely comes with other symptoms. Since you still get it with the car on, I'm not sure I can help you unfortunately.

[rix617]

After work today I decided to take a look under the car. I basically interpreted what the guy on e46fanatics called "steering rack bolt bushings" as simply the bolts that attach the rack to the subframe. They were not loose, but I removed them, wiped down the contact surfaces between the rack and the subframe, and the bolts themselves. After I replaced it all and tested it out the sound was gone. I don't really know how those bolts could cause the noise because there really isnt any room for play that I could feel in the attachment points. But if the noise really is gone then maybe there's something to what he said.

[YoitsTmac]

I'm glad you found your clunk! Now I'm definitely concerned about my rack bolts...I've removed mine a number of times, so now I'm a little concerned. I'm the worst mechanic I know! :)

[zhaireszhp]

happy you were able to resolve it, bmw engineering can really be a bitch sometimes lol

[Oli77]

That's n=2 for removing the bolts cleaning and retughtening. Easy enough and good to know.

[Will]

Glad you figured it out and it was a inexpensive fix!