Knocking sound from front of car when turning fully (not a diff issue)

[Seattle S65B40]

Sometimes when i'm parallel parking or making close to full turns of the steering wheel while stationary or rolling slowly, i hear a knock sound from the front of the car when going beyond one full turn of the wheel (either left or right, and either servotronic on or off). This isn't exactly a new issue, as I've noticed it since i've had the car. it is intermittent but with my warranty expiring early next year, I'd like to start looking into this.

Can someone confirm that this is normal, part of servotronic or some other function i don't have to worry about? If not, let me know so I can make an appointment for this. Steering feels fine otherwise, just this loud single knocking sound and when I parallel park or turn into my garage at a sharp angle is when it usually happens. Thanks.

[JoLo]

I have the same noise and my car is brand new, im hoping its just the way it is. Because it my dads e46 m3 made a noise when turning tight slowly.

[John Tanglewood]

I get what sounds like a rubbing noise, but mine sounds like it comes from the rear.

As I'm only running 10mm spacers in the rear, I know I'm not rubbing. But I would like to know what is causing it.

[bsiciliano]

If it is coming from the rear on really tight turns, then you may need to go to the dealer to get them to add the "special" rear differential fluid. If you search there is a service bulletin on it. OP, are you sure you problem is in the front and not the rear?

My office has a 4 level parking lot with tight spiral ramps. I noticed a creaking/rubbing noise every time I pulled into the office. I printed out the post that had a link to the SB and took it to the dealer. They changed the fluid while I waited - 45 minutes. Problem disappears after a few hundred miles.

[Seattle S65B40]

Originally Posted by John Tanglewood

I get what sounds like a rubbing noise, but mine sounds like it comes from the rear.

As I'm only running 10mm spacers in the rear, I know I'm not rubbing. But I would like to know what is causing it.

Never noticed any rubbing before, but I don't have spacers.

Originally Posted by bsiciliano

If it is coming from the rear on really tight turns, then you may need to go to the dealer to get them to add the "special" rear differential fluid. If you search there is a service bulletin on it. OP, are you sure you problem is in the front and not the rear?

My office has a 4 level parking lot with tight spiral ramps. I noticed a creaking/rubbing noise every time I pulled into the office. I printed out the post that had a link to the SB and took it to the dealer. They changed the fluid while I waited - 45 minutes. Problem disappears after a few hundred miles.

Yes definitely from front. It sounds like someone in the engine bay or front wheel well is banging one time on stack of papers that are sitting on a metal desk. It arises out of turning the the steering wheel and i almost hear it or feel it again as I come back past that point to straighten the wheel. Definitely don't think it is the diff issue, as the dealer already took care of that as part of the Cowbell Noise investigation a while back...

[Skippy989]

Originally Posted by John Tanglewood

I get what sounds like a rubbing noise, but mine sounds like it comes from the rear.

As I'm only running 10mm spacers in the rear, I know I'm not rubbing. But I would like to know what is causing it.

I had the same thing on mine. A rubbing sound on full lock. You need the M3 diff service and the "special" diff oil. Its free if you have a warranty. It also took some of the clunkiness the transmission had on cold starts away.

[John Tanglewood]

Originally Posted by Skippy989

I had the same thing on mine. A rubbing sound on full lock. You need the M3 diff service and the "special" diff oil. Its free if you have a warranty. It also took some of the clunkiness the transmission had on cold starts away.

Ah, thanks for this!!

[JCtx]

Originally Posted by Seattle S65B40

i hear a knock sound from the front of the car when going beyond one full turn of the wheel (either left or right, and either servotronic on or off).

Please provide more details. Does it make the sound wiith the car stopped? Or only when moving? If only moving, you can discard the steering. But you also have to make sure it's not differential 'crunching' reflecting the sound to the front; otherwise it'd have to be a suspension bushing. And finally, when car 'crunches', if you immediately move forward without moving the steering wheel, does it make the same sound at the same spot again? Or only when going in reverse?

The first thing I'd do is change the differential oil with either the proper BMW one (the expensive one), or with RP 75/140 max gear, like I did. And that's good that you're looking into this. Oh, and a video clip would be awesome, to more or less hear how it sounds like. Take care.

[Seattle S65B40]

Originally Posted by elp_jc

Please provide more details. Does it make the sound wiith the car stopped? Or only when moving? If only moving, you can discard the steering. But you also have to make sure it's not differential 'crunching' reflecting the sound to the front; otherwise it'd have to be a suspension bushing. And finally, when car 'crunches', if you immediately move forward without moving the steering wheel, does it make the same sound at the same spot?

Thanks for chiming in JC. I think i've only ever seen it while stopped or really low speeds. I will see if I can make a video of this tonight. Example:

Parallel parking:

pull past the spot (on my right)

Full lock to right as I begin to back into spot. No issues here.

Get to the point where I need to go forward and begin turning in the other direction close to full lock. **POP** and I will hear it before reaching steering direction that i want.

Then i move forward. if I need to do it again, I will often here the pop again when turning the other way past the exact same point where it popped on me the first time.

It has also happened while rolling really slow and turning to go in or back out of my garage if I'm coming out or going in at a sharper angle because of another car behind me etc.

Really don't think it's the diff. I had that service done in February and it has done it before and after.

Originally Posted by JoLo

I have the same noise and my car is brand new, im hoping its just the way it is. Because it my dads e46 m3 made a noise when turning tight slowly.

Does this still sound like what you're experiencing?

[bluekn8286]

Originally Posted by Seattle S65B40

Thanks for chiming in JC. I think i've only ever seen it while stopped or really low speeds. I will see if I can make a video of this tonight. Example:

Parallel parking:

pull past the spot (on my right)

Full lock to right as I begin to back into spot. No issues here.

Get to the point where I need to go forward and begin turning in the other direction close to full lock. **POP** and I will hear it before reaching steering direction that i want.

Then i move forward. if I need to do it again, I will often here the pop again when turning the other way past the exact same point where it popped on me the first time.

It has also happened while rolling really slow and turning to go in or back out of my garage if I'm coming out or going in at a sharper angle because of another car behind me etc.

Really don't think it's the diff. I had that service done in February and it has done it before and after.





Does this still sound like what you're experiencing?

I experience something similar; however, it only happens in colder temps (in the morning when pulling out of the garage) and on a specific incline. I can't hear a thing when the road is straight.

Its not bothering me too much because it doesn't happen often enough for me to worry.

Hope this helps.

[Singletrack]

I've heard the same thing in parking garages...haven't heard it in a while though. I have had to bend back the dust shields on my front brakes multiple times - they make some interesting noises when not aligned properly. Not sure if that sound is still present though to be honest.

[Seattle S65B40]

For those of you experiencing this, take it in. It's not normal. My car doesn't make sound now when I make any sort of turn and the wheel feels more fluid past a full turn. Lower joint replacement fixed the problem for me.

[Singletrack]

Originally Posted by Seattle S65B40

For those of you experiencing this, take it in. It's not normal. My car doesn't make sound now when I make any sort of turn and the wheel feels more fluid past a full turn. Lower joint replacement fixed the problem for me.

Thanks for info - will now have to try to replicate again.

EDIT - if not too much trouble, could you let us know what parts they replaced from the work order?

[jeff@autocouture]

i had that, it was my belts going bad, have it checked out, if thats it its a cheap fix