[ddroze]

Ok, guys, I am stumped and so are the mechanics. 2009 335d.

When I make a decent left with some pressure pulling you to the right, it sounds like the front wheel side (could be rear?) grinds like a sound of sliding on gravel. Our guess was the wheel bearing was going bad. No matter how well i balanced the tires that side caused wobbling. That turned out to be the control arm bolt coming loose though so that part is fixed.

I put on new tires because i needed them anyway, so that's not it. I put on new rotors and pads with a Stop Tech kit because I also needed those, that's not it. I tried the wheel bearing AND hub combo, that's not it (unless its the rear and sound are traveling to the front.) No rubbing on tires from what i can tell. No rubbing in the wheel-well or on the wheels. This has been going on for i dont know, maybe a year?

Is there something ringing a bell here that someone has heard of or something common? If i turn from a light to the left, eventually i hit that apex and its like pressure/force then causes the sound. I can let up and steer into it a little and it stops then steer back and its back. It gets harsher as the force increases. Limited-slip but only when turning right? We are lost. I tried to record it but you cant hear it well.

[ddroze]

Also, I do have upgraded wheels but I cant recall if it started at the same time? They are a +30 offset all around and seem to be just fine....

[relative4]

Does the noise happen with the sway bar disconnected?

[Soravia]

Your car is 11 years old. Check all the bushings that are not solid rubber type. They might have failed inside.

I'm replacing all of them on my car. every single control arm. I know they will fail soon enough closer they get to 100k.

[juld0zer]

Should be pretty easy to spot a tyre contact mark on the wheel arches, suspension or control arms

[ddroze]

I really don't believe its bushings. I looked around most of those areas and they looked fine. But that would mean rubbing and its weird because there is no rubbing anywhere. It sounds rotational though and rough.

No one with a common issue? I was hoping it was easily identified as some weird BMW thing.

[juld0zer]

Originally Posted by ddroze

Ok, guys, I am stumped and so are the mechanics. 2009 335d.

When I make a decent left with some pressure pulling you to the right, it sounds like the front wheel side (could be rear?) grinds like a sound of sliding on gravel. Our guess was the wheel bearing was going bad. No matter how well i balanced the tires that side caused wobbling. That turned out to be the control arm bolt coming loose though so that part is fixed.

I put on new tires because i needed them anyway, so that's not it. I put on new rotors and pads with a Stop Tech kit because I also needed those, that's not it. I tried the wheel bearing AND hub combo, that's not it (unless its the rear and sound are traveling to the front.) No rubbing on tires from what i can tell. No rubbing in the wheel-well or on the wheels. This has been going on for i dont know, maybe a year?

Is there something ringing a bell here that someone has heard of or something common? If i turn from a light to the left, eventually i hit that apex and its like pressure/force then causes the sound. I can let up and steer into it a little and it stops then steer back and its back. It gets harsher as the force increases. Limited-slip but only when turning right? We are lost. I tried to record it but you cant hear it well.

Help me to get a better understanding - what do you mean by decent left with pressure pulling to the right? A hard left turn around a sloped corner?
What tyres and what wheels? Could it be understeer? Can you reproduce it stationary by turning the wheels lock to lock? Examine the front strut top mounts as with age and wear from rough roads, they can fail or make noise.

[PerfectAce]

It's your motor mounts. Specifically, your passenger side mount -- that one always wears quicker than the other. But replace them both.

Turning to the left causes weight transfer to the right putting more pressure on the mount. The worn/collapsed inner rubber of the mount can no longer fully support the weight of that oil burning boat anchor up front and what you are hearing is the metal-on-metal grinding of the mounting arm against the mount housing.

This thread should be helpful: https://www.e90post.com/forums/showthread.php?t=1312318

There's another thread somewhere in the diesel forum that I can't find right now with a picture that someone took of their old passenger side motor mount showing where the metal-on-metal contact had ground down an edge of the mount housing.

[ddroze]

Originally Posted by juld0zer

Help me to get a better understanding - what do you mean by decent left with pressure pulling to the right? A hard left turn around a sloped corner?
What tyres and what wheels? Could it be understeer? Can you reproduce it stationary by turning the wheels lock to lock? Examine the front strut top mounts as with age and wear from rough roads, they can fail or make noise.

AS a left I mean if you were sitting at a stoplight to turn left across a good size intersection (enough to build some sort of speed) and then begin to go, you will build up force through speed so when you make the left turn, the body would want to roll to the right. Once you get enough force WHILE accelerating (this seems to be the weird part) then you will hear it. I cannot produce it stationary. It seems if i make a hard left WITHOUT accelerating but moving with foot off the gas, I cannot reproduce the sound. This makes me feel like its some sort of traction control item but it still does it with DSC off as well.

As for the motor mount, it doesn't seem like that would be it either it would still make that sound with a hard left whether I was accelerating or not. Or maybe it torques the motor when I do. I will explore your link.

[PerfectAce]

Originally Posted by ddroze

As for the motor mount, it doesn't seem like that would be it either it would still make that sound with a hard left whether I was accelerating or not. Or maybe it torques the motor when I do. I will explore your link.

I know it sounds weird, but if you had posted your question in the diesel forum, you would've had a dozen replies within a day telling you it's your motor mounts. The diesel mounts are different than the units on gassers -- ours are vacuum controlled. There's also a chance that it's just the vacuum line running to your mount that's damaged and you have a leak, but given the age of the car, I would bet that the mount itself is past its expiration date.

Found the picture I was referring to earlier: https://www.e90post.com/forums/showthread.php?t=1243089 See post 16.

Also: https://www.e90post.com/forums/showthread.php?t=1516122 The title of that thread is literally: "2011 335d Noise while turning left under acceleration" lol

[juld0zer]

Petrol models with high mileage can have collapsed engine mounts also, and it is usually the right side mount.

You can also confirm a worn mount visually by looking for abrasion marks on the engine bracket. When the mount has collapsed, the engine's weight sits on the rubber pads. A worn but not failed one may just have witness marks (contact marks).
You can also check by loading up the drivetrain by firmly pulling up the park brake, left foot firmly on brake pedal whilst accelerating in D or R. You don't need to accelerate much. Do this test with an assistant standing beside the engine bay and if the mount is shot, the engine should want to jump out of the engine bay

[Wolf 335]

I’m experiencing something similar at the moment but I’m certain that in my case it is the front right wheel bearing. I got a set currently in transit from fcpeuro. Will update after install.

I have a howling and grinding in a straight line at any speed. If I turn the steering wheel even slightly to the right it changes the noise making it almost disappear.

Have someone drive you car and replicate the maneuver while you sit in the back with the rear seat folded down in order to listen and isolate the rear bearing noise.

Good luck and keep us posted.

[ddroze]

Originally Posted by PerfectAce

I know it sounds weird, but if you had posted your question in the diesel forum, you would've had a dozen replies within a day telling you it's your motor mounts. The diesel mounts are different than the units on gassers -- ours are vacuum controlled. There's also a chance that it's just the vacuum line running to your mount that's damaged and you have a leak, but given the age of the car, I would bet that the mount itself is past its expiration date.

Found the picture I was referring to earlier: https://www.e90post.com/forums/showthread.php?t=1243089 See post 16.

Also: https://www.e90post.com/forums/showthread.php?t=1516122 The title of that thread is literally: "2011 335d Noise while turning left under acceleration" lol

Just an update so others have answers. I don't use this forum much and didn't realize the diesel-only section. Anyway, it was the passenger motor mount. It collapsed and grinds on hard left turns. Fairly easy to replace but you need to have an engine hoist or engine bar to hold the motor up from the top and drop the subframe a little. I jacked my car WAY up with huge stands to give some room and use a jack to lower the sub frame some. Good videos on youtube for this. Make sure you order the right parts! They are different part numbers on the diesel FOR SURE!