A rattle started happening after I overshot a couple of ramps several months ago, but has gotten louder recently. It happens over most roads at speeds below ~45mph, and rarely above 25. It sounds medium-deep but muffled - not metallic or heavy, and is more of a rapid bonk than a buzz. I know that rattles in cars can be very misleading, but the best I can tell is that it's coming from the front left, and is more internal than external. It's quiet enough that with the windows down, the engine and ambient noise drown it out.

I rebuilt my front suspension (all 4 arms, the right tierod, both wheel bearings), and it didn't go away. It got worse, I think, after 3200 high-speed miles from Florida to San Francisco. Almost all of that was on the highway, and it felt really bad when I got to the city itself.

Steering has no effect, neither does acceleration or braking. It seems to be set off most by tiny, otherwise imperceptible bumps, and isn't louder over bigger ones. The only change is that it's more frequent on broken roads, especially cobblestone.

I've been trying to do a sort of "forensic analysis" of what happened when I slammed down on the ramps, and I've run into some questions:

Could a large, sudden extension of the strut assembly cause physical shock to loosen or break something in the strut housing or mount, or are they designed to handle that (even after 176k miles)?

Do shock absorbers absorb short, small, sudden bumps, or just bigger ones, transmitting the tiny ones to the car's body (where they're too small to be felt)?

Since steering doesn't affect it, can I safely assume that it has nothing to do with any steering components?

What's between the strut mount and the firewall, besides the LKM and fuse box?

Any and all help would be much appreciated - this is driving me nuts, and even if I were willing to throw parts at it, I don't even know where to begin.

did you ever figure this out? I'm curious

A rattle started happening after I overshot a couple of ramps several months ago, but has gotten louder recently. It happens over most roads at speeds below ~45mph, and rarely above 25. It sounds medium-deep but muffled - not metallic or heavy, and is more of a rapid bonk than a buzz. I know that rattles in cars can be very misleading, but the best I can tell is that it's coming from the front left, and is more internal than external. It's quiet enough that with the windows down, the engine and ambient noise drown it out.

I rebuilt my front suspension (all 4 arms, the right tierod, both wheel bearings), and it didn't go away. It got worse, I think, after 3200 high-speed miles from Florida to San Francisco. Almost all of that was on the highway, and it felt really bad when I got to the city itself.

Steering has no effect, neither does acceleration or braking. It seems to be set off most by tiny, otherwise imperceptible bumps, and isn't louder over bigger ones. The only change is that it's more frequent on broken roads, especially cobblestone.

I've been trying to do a sort of "forensic analysis" of what happened when I slammed down on the ramps, and I've run into some questions:

Could a large, sudden extension of the strut assembly cause physical shock to loosen or break something in the strut housing or mount, or are they designed to handle that (even after 176k miles)?

Do shock absorbers absorb short, small, sudden bumps, or just bigger ones, transmitting the tiny ones to the car's body (where they're too small to be felt)?

Since steering doesn't affect it, can I safely assume that it has nothing to do with any steering components?

What's between the strut mount and the firewall, besides the LKM and fuse box?

Any and all help would be much appreciated - this is driving me nuts, and even if I were willing to throw parts at it, I don't even know where to begin.

Dollars to donuts it was a bad strut bearing plate.

Uh...what's a strut bearing plate? The thingy that attaches the strut to the tower? Or something closer to the axle?

Uh...what's a strut bearing plate? The thingy that attaches the strut to the tower? Or something closer to the axle?

It's above the strut.

Did you check the sway bar link?

The link is indeed slightly loose, and I have two replacements. I'm waiting to hear back from a BFc member who offered to loan me a tierod puller, so I can replace those and see if it's the source. I doubt it is, though, because of where the sound seems to originate, and how it started.

i just replaced the front sway links on my 535iM, I didn't need a puller or anything, just tap them out. Really easy. One thing, make sure you torque them down correctly (you'll have to turn the steering wheel to get the torque wrench in there right), then drive about 20 miles, then torque them again. I just replaced mine as I said, and when I went to replace my thrust arms, control arms, and tie rod ends, i noticed my sway links were loose and clunking! hope that helps.

I just replaced my end link too. It was making subtle noises over smaller bumps. Perfect now!!!

Ordered a 2-jaw gear puller. Hopefully, it'll work on the links as well.

I got very quickly turned off to pickle forks the first time I tried to use them - got nowhere but sweaty. Popped on the 2-jaw thing and it worked like a charm. Sounded like a gunshot, though :).

I am having a problem like this. I get a klunking noise at seemingly random times, as in there was no pattern I could distinguish. I took it into a local shop to see if they could find out where it was coming from.

It turns out that the Strut Bearing had dried out and seized causing the spring to rotate instead of the bearing. So the pressure would build up and instead of the bearing moving to relieve the pressure the spring would move, causing the klunk. You could see the wear on the spring from this movement.

I am ordering a pair of strut bearings, but I have to find out how hard it is to change those myself.

also please check the pitman, steering arms and the "dogbones" (rear Pitman arms) the back

Hello Moroza,
I had a similar noise - does it sound like it is coming from the bulkhead behind the steering wheel / dash?
My noise was coming from the scutchion plate beneath the wiper arms where the wiper shafts poke through the cowl top.
There are several little plastic clips holding the plastic leaf screen in place, these had worked a little loose. The clips are like a split pin which opens into a square hole when you push the pin into the centre of the clip. I could replicate the 'rattle' by gently tapping the leaf screen with my fingers. The answer was to buy a bag of new clips (they come in bags of twenty from the stealership). Remove the wiper arms and then remove the plastic pins to remove the leaf screen, stick some very thin anti rattle felt / foam strips under the leaf screen so that it sits on the windscreen then put the new clips in to secure it back down.
Removing the original pins is tricky - they will be old and brittle use pliers to pull out the pin from the centre of the clip - they look like about 6mm x 8mm grey / black plugs.

good luck - hope you find the problem.

i just replaced the front sway links on my 535iM, I didn't need a puller or anything, just tap them out. Really easy. One thing, make sure you torque them down correctly (you'll have to turn the steering wheel to get the torque wrench in there right), then drive about 20 miles, then torque them again. I just replaced mine as I said, and when I went to replace my thrust arms, control arms, and tie rod ends, i noticed my sway links were loose and clunking! hope that helps.
Sorry to hijack, but does anybody know the Torque setting for the sway bar links?

Sorry to hijack, but does anybody know the Torque setting for the sway bar links?
59Nm/43Ft-Lb per Bentley Manual

Many thanks, replaced mine yesterday. So will torque them up tomorrow.

you might need a pair of pliers to hold the ball joint while you tighten the nut.. just don't bust the ball joint!

16mm wrench fits on the back to hold the ball part whilst you torque :)

I'm currently replacing the swaybarlinks and the left tierod. Who the hell thought it was a good idea to use a 16mm nut on one side of the ball joint thread, and 17mm on the other? Why not 17 for both, or at least a commonly-used size on each, thus saving me the trouble of finding a ride to a hardware store to get a tool I'm probably never going to use again, leaving my car jacked up lopsided until said store opens on Monday? :mad

Anyone have any pointers on loosening the top ball joint nut, without removing or bending (as I did) the brake rotor dust cover?

I figure if replacing these doesn't do it, it's the strut bearing plate. The entire strut is kinda rusty and may deserve whole replacement. Any ideas what I'd pay for a clean one from a parts car or salvage yard? I'll be replacing springs and shocks anyway, so I just need the other hardware.

A rattle started happening after I overshot a couple of ramps several months ago, but has gotten louder recently. It happens over most roads at speeds below ~45mph, and rarely above 25. It sounds medium-deep but muffled - not metallic or heavy, and is more of a rapid bonk than a buzz. I know that rattles in cars can be very misleading, but the best I can tell is that it's coming from the front left, and is more internal than external. It's quiet enough that with the windows down, the engine and ambient noise drown it out.

I rebuilt my front suspension (all 4 arms, the right tierod, both wheel bearings), and it didn't go away. It got worse, I think, after 3200 high-speed miles from Florida to San Francisco. Almost all of that was on the highway, and it felt really bad when I got to the city itself.

Steering has no effect, neither does acceleration or braking. It seems to be set off most by tiny, otherwise imperceptible bumps, and isn't louder over bigger ones. The only change is that it's more frequent on broken roads, especially cobblestone.

I've been trying to do a sort of "forensic analysis" of what happened when I slammed down on the ramps, and I've run into some questions:

Could a large, sudden extension of the strut assembly cause physical shock to loosen or break something in the strut housing or mount, or are they designed to handle that (even after 176k miles)?

Do shock absorbers absorb short, small, sudden bumps, or just bigger ones, transmitting the tiny ones to the car's body (where they're too small to be felt)?

Since steering doesn't affect it, can I safely assume that it has nothing to do with any steering components?

What's between the strut mount and the firewall, besides the LKM and fuse box?

Any and all help would be much appreciated - this is driving me nuts, and even if I were willing to throw parts at it, I don't even know where to begin.


with all due respect, how did you 'overshoot' a set of ramps...?

id say that its probably your strut mounts. bma has them for about 45$ cheap, to 120$ or so for oem. you also mentioned that your questioning your struts; replace tham as well. they have to come out anyway if you do in fact have to replace the mounts.

either that or you might be going back for another 17mm wrench...get over it :)

First time I did it I was so happy to have found the flats that I didn't care what size they were....

with all due respect, how did you 'overshoot' a set of ramps...?

See below.


id say that its probably your strut mounts. bma has them for about 45$ cheap, to 120$ or so for oem. you also mentioned that your questioning your struts; replace tham as well. they have to come out anyway if you do in fact have to replace the mounts.Just to clarify, you mean the strut (metal tube housing the shock absorber, carrying the spring, attached to the steering knuckle, stub axle, and swaybarlink), and not the shock absorber? My shocks are getting upgraded, almost certainly to Konis. Springs too, not sure which (Vogtland if I can find a thicker spring pad so they don't sit quite so low). The strut itself looks to be in the category of "Things to replace in the course of a full restoration", rather than "Things to replace because they're failing or ugly". Just how much it's in the former category depends on what I'd expect to pay for a rust-free pair of used ones. Any ideas?

Where in Ohio are you, btw?

either that or you might be going back for another 17mm wrench...get over it :)

First time I did it I was so happy to have found the flats that I didn't care what size they were....
Except that BMW provided a 17mm wrench with the car, and it's a fairly common size. I don't think I've ever seen a 16mm spanner. I think I'll just try to get a Vicegrip with a flatter nose.

See below.

Just to clarify, you mean the strut (metal tube housing the shock absorber, carrying the spring, attached to the steering knuckle, stub axle, and swaybarlink), and not the shock absorber? My shocks are getting upgraded, almost certainly to Konis. Springs too, not sure which (Vogtland if I can find a thicker spring pad so they don't sit quite so low). The strut itself looks to be in the category of "Things to replace in the course of a full restoration", rather than "Things to replace because they're failing or ugly". Just how much it's in the former category depends on what I'd expect to pay for a rust-free pair of used ones. Any ideas?

id think the strut mount would go bad before the strut itself, but i could be wrong... its only a bearing and some rubber; much weaker than the strut itself
which is steel.


Where in Ohio are you, btw?
i was in the cleveland area.


Except that BMW provided a 17mm wrench with the car, and it's a fairly common size. I don't think I've ever seen a 16mm spanner. I think I'll just try to get a Vicegrip with a flatter nose.

i dont think id try vise grips. worst case scenario, try a crescent wrench, if you can get it to fit. for me, i just buy what i need. i do all my own work on all my cars and equipment (i run a small concrete and hauling business), so im always using larger sockets and wrenches, so for me, theyre worth buying.

[QUOTE=moroza;11921963]See below.

Just to clarify, you mean the strut (metal tube housing the shock absorber, carrying the spring, attached to the steering knuckle, stub axle, and swaybarlink), and not the shock absorber? My shocks are getting upgraded, almost certainly to Konis. Springs too, not sure which (Vogtland if I can find a thicker spring pad so they don't sit quite so low). The strut itself looks to be in the category of "Things to replace in the course of a full restoration", rather than "Things to replace because they're failing or ugly". Just how much it's in the former category depends on what I'd expect to pay for a rust-free pair of used ones. Any ideas?


i see the pic; but forgive me, i guess i still have a hard time understanding how you 'overshot' the ramps...? ive never heard of anyone doing that, but be careful next time. how did you get the car off..? floor jack?

i see the pic; but forgive me, i guess i still have a hard time understanding how you 'overshot' the ramps...? ive never heard of anyone doing that, but be careful next time. how did you get the car off..? floor jack?

Easy, just drive the rear wheels up and over the same ramps. :D :shifty

Don't forget to yell "Hey, y'all watch this..." before hitting the gas.

Tried flat-nosed Vicegrips, and they worked wonderfully. I can't justify buying a tool I'll never forseeably use again, over one as versatile as a good set of locking pliers.

I overshot them because I misjudged where the front tires were, and didn't brake in time. Actually, the front tires were perched on the edge of the ramps, before I let go of the brakes. In hindsight, I should've stayed on the brakes and risked a little brake and clutch wear, and just backed up. I used the factory jack to lift the car enough to slide them out. I don't intend to repeat this...

Easy, just drive the rear wheels up and over the same ramps. :D :shifty

Don't forget to yell "Hey, y'all watch this..." before hitting the gas.

This is why you drive a loaner. ;)

Fixed!

Turned out to be the port swaybarlink. I'm somewhat surprised, because though I knew it had play in it, the noise sounded much closer to the driver, and much more internal.

Strut plate will wait until shocks and springs get replaced.

I also replaced the port tierod, and extended a bit for more toe-in. Seems to've solved a bit of highway wander. Before I get to work fiddling with the other one to center the steering, anyone care to tell me if DIY alignments are dangerous for some reason?

it's not dangerous as long as you know what you are doing.
there is lots of talk about pre loading your ride with approximate weights in both the driver's side and passenger side depending upon the average use your vehicle takes.
good luck.
Pete

i too have a sound from the front suspension. i replaced the control arms, and struts on both sides a few months back. it rode perfect for about 6 months, no noise, so smooth. then i started getting a chatter from the front suspension. i tightened the top bolts on the strut mounts under the hood and the driver side is now quite. the passenger side is still clanking, mostly on any change in the road. a pothole, manhole cover, speed bump. ive replaced both swar bar links within the last month and it was a little better for a day or so then its clanking again. should i try to tighten the sway bar link on that side again or what?

sorry to hijack. anyone have any ideas? im going to put it on the jackstand today and tighten the top strut mount with the wheel off and also tighten the sway bar link. now this noise started a few months after i put new struts on, think it could be coming from something inside where the spring mounts tot he strut?

not that anyone cared, but i found the problem. the 19 or 22mm bolt holding the bottom of the strut to the strut mount is completely off. have to take off the entire assembly and get a wrech big enough to make it super tight this time. gonna tighten the other side as well, as some thread s are showing.