Suspension Knocking clunking noise from front end at low speed

[bmwahba46]

Greetings,

The car has 114k miles and my front end suspension is making a slight "knocking" or clunk noise at low speeds. To me it sounds like a bad ball joint. I can only notice it on the drivers side, however I've never really tested to hear it from the passenger side.

I am in the process of changing the front thrust arm bushings, due to some vibration caused when braking lightly at speeds of around 40 mph. Some previous work that has been done on the front end suspension was front tie rods and new Bilstein HD struts, (and thrust arm bushings soon).

So what could be causing this? Will replacing the complete thrust arms fix my problems? Or is there something else that could be causing it? As of now I only plan to replace the bushings on my thrust arms, but if anyone thinks that replacing the whole thrust arm assembly fixes this issue, let me so know I can do them together. Thanks!

[clarkitect]

I have the same issue.

Could be a number of things: ball joints, sway bar end links, sway bar bushings, strut mounts, spring perches.

Best thing to do is jack up the front end and check all the above with a pry bar to see if you notice any movement. I've done just that and as a result have replaced the sway bar bushings and links and both lower control arms (not the trust arms) and still have some clunking. I'm thinking strut mounts but I think those are tough to diagnose.

First thing to check is the sway bar links imo.

Another possibility is rattling calipers or brake pads. If the noise goes away when you apply the brakes, it would indicate an issue with calipers/pads.

So basically you'll have to do some forensic investigating to find the root of the problem.

[topaz540i]

Dont forget to check if its the plastic rattling. I couldnt figure out why my driver side sounded like it was popping then i reealizezed it started when i put my undershield back on. Ends up my bumper and shield are a little loose in the front.

[bmwahba46]

Thanks for the replies,
I'll take a look around and see if I can find anything loose or wobbly.

Also, do you guys think it would be a good idea to replace my whole thrust arm assembly or should I just replace the bushings? At 114k miles would it make more sense to replace the whole thing and get it over with?

[RVAE34]

It's easier to replace the thrust arm. And +1 to end links as another potential cause. Usual suspects are thrust arm, ball joints and end links.

[bmwahba46]

It's easier to replace the thrust arm. And +1 to end links as another potential cause. Usual suspects are thrust arm, ball joints and end links.

I see, ok.

Lemfoerder thrust arms and bushings should be fine? Are powerflex bushings worth the extra $100 bucks?

And these are the sway bar end links in question:
http://www.bavauto.com/lview.asp?img...4-02_img01.jpg

Are they difficult to install?

[RVAE34]

I tried powerflex in my E34 and didn't like them. I am not sure if Moosehead makes the spherical bushing thrust arms for the E39 like they do in the E34 but I loved those. Otherwise, I would think Lemforder would be fine.

[bmwahba46]

Thanks RVAE.

Before I jump the gun on any of the other parts I'm going to install the thrust arms and see where that puts me. Hopefully it gets rid of the shimmy while braking, and possibly the clonk sound. If that doesn't solve the issue then I'll order the sway bar links.

edit:
Is a wheel alignment necessary after replacing thrust arms? How about end links? should I just replace both at once?

[RVAE34]

Sway bar end links are super cheap and easy so I may suggest starting there. You should be able to grab the end link rod and give it a good shake. If you feel play in the joints at each end, that is your problem. I like to replace all my end links about once every 2 years as they tend to go quickly. When I got my touring, they were pretty bad. IIRC, it was only about $50-60 for all 4 and only took me 45 min to do all of them.

[ELA]

I've always known suspension problems to make "creaking" sound, but there was another thread here that makes "clunking" noise and the cause was busted strut mount.

[bmwahba46]

I should also mention that it seems that whenever the clunk noise happens, I can sort of feel it under the floorboards right by the pedals. That makes me think it's not a strut mount, but rather a bad balljoiint or bushing of some sort. Anyone else experience this?

[topaz540i]

Prob the thrust arm bush.

[Jason5driver]

I tried powerflex in my E34 and didn't like them.
I am not sure if Moosehead makes the spherical bushing thrust arms for the E39 like they do in the E34 but I loved those.
Otherwise, I would think Lemforder would be fine.

You mean these...?
(Moosehead Spherical Upper Control Arm Bushings):
http://mooseheadengineering.com/#!/~...126&id=6647004

And, I agree, I would highly suspect the sway bar links...
Especially if the suspension has been lowered...

Have the strut mounts been replaced?
And/ or have the Tie Rods been replaced as well...?

You can usually check what is happening with the suspension by jacking up a corner of the car in question, and pushing/pulling the wheel/tire in and out.
If you feel or hear clunking, or get movement, then you know something is bad...

If there is movement and/or clunking, you can have a buddy help pin-point where it is coming from while you are moving the wheel/tire back and forth...

Thanks!
Jason

[RVAE34]

I wonder if the thrust arm bushing test is the same for the E39 as it was the E34. In the E34, you would drive slow at parking lot speeds. And continually hit and release the brakes in succession. If you felt a thud after each time you release the brake, you would know it was the thrust arms.

[theWalkinator]

My problem is clunking coming from rear end, checked everything all looks fine and tight, someone suggested that it might be the break pads so I am going to check that next.

[RVAE34]

checked the subframe bushings, diff mount or rear endlinks?^

[Jason5driver]

My problem is clunking coming from rear end, checked everything all looks fine and tight, someone suggested that it might be the break pads so I am going to check that next.

Check the Rear Ball Joints and Rear Upper Control Arms...
When they are bad, it makes the car's handling all squirrely...

[theWalkinator]

checked the subframe bushings, diff mount or rear endlinks?^

Subframe bushings are fine, diff mount is fine too, thrust arm ball joints are fine, end links looks fine, only wishbone ball joint boot has crack on both side, but twisted with hand, tiny little play so not sure if that will produce the clunking noise.

[bmwahba46]

You mean these...?
(Moosehead Spherical Upper Control Arm Bushings):
http://mooseheadengineering.com/#!/~...126&id=6647004

And, I agree, I would highly suspect the sway bar links...
Especially if the suspension has been lowered...

Have the strut mounts been replaced?
And/ or have the Tie Rods been replaced as well...?

You can usually check what is happening with the suspension by jacking up a corner of the car in question, and pushing/pulling the wheel/tire in and out.
If you feel or hear clunking, or get movement, then you know something is bad...

If there is movement and/or clunking, you can have a buddy help pin-point where it is coming from while you are moving the wheel/tire back and forth...

Thanks!
Jason

Front tie rods were replaced, yes. Strut mounts have not. I did try jacking up the drivers side and didn't get much play.

I'm going to do the install on the thrust arms and see where that puts me first.

Does anyone know if a wheel alignment is needed after thrust arm replacement?
Thanks!

[Jason5driver]

Front tie rods were replaced, yes. Strut mounts have not. I did try jacking up the drivers side and didn't get much play.

I'm going to do the install on the thrust arms and see where that puts me first.

Does anyone know if a wheel alignment is needed after thrust arm replacement?
Thanks!

An alignment should be done any time anything is replaced/ messed with on the suspension.
If you are replacing the control arms, then yes, you will need an alignment.

[bmwahba46]

An alignment should be done any time anything is replaced/ messed with on the suspension.
If you are replacing the control arms, then yes, you will need an alignment.

Upper control arm, thrust arm, whatever you wanna call it. However I thought you only had to do an alignment for lower control arms.

[Jason5driver]

Upper control arm, thrust arm, whatever you wanna call it. However I thought you only had to do an alignment for lower control arms.

ANY replacement of suspension components requires an alignment, except sway bars or sway bar links.

[bmwahba46]

ANY replacement of suspension components requires an alignment, except sway bars or sway bar links.

Gotcha, thanks!

Only place around me that is able do alignments on these cars is the Bmw dealership

[IJustDrive]

Just replaced upper and lower control arms at about 90k and mine is starting to get get worse. Exact same symptoms as you describe. Only thing left is sway bar ends and sub frame bushings. Gonna try sways first.

[Jason5driver]

Gotcha, thanks!

Only place around me that is able do alignments on these cars is the Bmw dealership

Did you look here for some mechanics...?
I do not know where you are at in Ohio...
http://www.bimmershops.com/bmwshops/ohio/

http://forums.bimmerforums.com/forum...us-OH-mechanic