Ball joint... but which one ?

[Claude]

I have a clunk noise coming from the front right side wheel (passenger side), new strut inserts just installed (had the clunk noise before the shock absorber fail) and no the strut collar nut (retainer nut) is not loose, the end link are good also, seems to be one of the ball joints, but which one this is tough to say, both doesn't show loose when tested with a crow bar and bushing of both arms the control one (lower one) and the strut one (the upper one) seem good.

I did the following test: in the drive way an other person run the right wheel over a bump ( a peace of 2x4 wood stud ) me being outside near the wheel, i can clearly hear the clunk and it clearly come from the steering plate area (where ball joints are fixed).

I notice that the clunk noise is a bit louder when the wheel fall down the stud that when it gets on the stud.

My strut arm and bushing (upper arm) have been change about 60000 km ago i don't know if the control arm have ever been change on that side of the car.

If i had to guest i would order a new strut arm and bushing, but i would prefer to be sure which arm is really defective before going ahead.

Any clue as how to test the ball joints so to be sure to change the proper one ?

[632 Regal]

Ball joint test is jab the brakes while going very slowly in reverse and forward. Heavy clunk or light> Light will usually be sway links. How do you know the strut collars are tight? Mine were tight but I torqued them an additional 1/2 turn to rid the clunk... I read you replaced the struts, just asking.

[Tiger]

Just change them all or otherwise you will be chasing all of them... one after another. Lower control arm would be my next bet.

[sal_park]

Any clue as how to test the ball joints so to be sure to change the proper one ?

I would agree with the post from Tiger - it's best to change them all (2x control arms, 2x trust arms) if you can. This job is quite a lot of work, so best to only do it once. (I did mine about 1 month ago)

The best clue you're going to get is that the bad ball joint(s) will have a ripped / broken rubber boot. The thrust arm ball joint will be fairly easy to see, but the control arm will be much more difficult because it is 'inside'* the steering plate

Also don't discount the anti roll bar (aka sway bar) drop links - these can easily be as noisy as the other ball joints and are easy to check - take one ball joint off** and see if the clunk has gone by driving over your 2'x4'.

* sort of.

** you'll need a (from memory) 15 or 17 mm flat open spanner for the back of the sway bar ball joint - it <B>really</B> won't fit well but will stop the ball joint turning.

sal

[Ferret]

** you'll need a (from memory) 15 or 17 mm flat open spanner for the back of the sway bar ball joint - it <B>really</B> won't fit well but will stop the ball joint turning.

I've just done these, and the lemfoerder parts come fitted with 16mm fittings - very annoying as 16mm is quite a rare size and you have to go digging to the bottom of the toolkit for the right spanner.

[Claude]

Ball joint test is jab the brakes while going very slowly in reverse and forward. Heavy clunk or light> Light will usually be sway links. How do you know the strut collars are tight? Mine were tight but I torqued them an additional 1/2 turn to rid the clunk... I read you replaced the struts, just asking.

I have this clunk noise since many months and before changing the insert (it failed leaking oil couple of weeks ago) it happend that i read one of your previous message telling our story about this infamous collar nut. So well before my insert failure and replacement we tight firmly (more than 1/2 turn) this collar nut and the clunk noise stay there So we remember that trick doing the insert replacement and tight the collar nut as much as we can !

[Claude]

i made some other tests on the road, here are the results:

1) At low speed (forward and reverse) i jam the break, no clunk no nothing, so according to Jeff comment that should confirm that the sway bar links are good and not the clunk source. Running on gravel road with regular but small bumps there is no clinking neither, i need to pass on a goob pot hole or greater step to hear the clunk.

2) Did some breaking tests first at moderate speed (at 60 km and at 100 km ), no vibration, straigth stops.

3) I noticed that some time (1 out of 5) there is a wheel vibration at the same time as the clunking noise (on the passenger side, the one where i have the clunk noise) when i do break but in the following conditions: at low speed (below 40 km) and with very light breaking, just touching the break pedal a bit. Seems to be more noticeable when breaking when turning on the left... didn't made enough tests to be completly sure of this one.

Question always the same, if ball a bad ball joint is the cause of that clunk noise and those low speed vibrations, what's the most probable bad one ? The lower control arm one or the upper trust arm one ?

Again prying those ball joint when no load on the front of the car, they both seems OK, but noise coming front there and one of those is the culprit... but which one ? For sure changing both control arms amy solve the problem, but i will be better of replacing only the defective one.

[Tiger]

i made some other tests on the road, here are the results:

1) At low speed (forward and reverse) i jam the break, no clunk no nothing, so according to Jeff comment that should confirm that the sway bar links are good and not the clunk source. Running on gravel road with regular but small bumps there is no clinking neither, i need to pass on a goob pot hole or greater step to hear the clunk.


This is wrong. Sway bar links only make noise upon potholes. No braking is going to cause the sway bar link to clunk or clink on you.

2) Did some breaking tests first at moderate speed (at 60 km and at 100 km ), no vibration, straigth stops.

3) I noticed that some time (1 out of 5) there is a wheel vibration at the same time as the clunking noise (on the passenger side, the one where i have the clunk noise) when i do break but in the following conditions: at low speed (below 40 km) and with very light breaking, just touching the break pedal a bit. Seems to be more noticeable when breaking when turning on the left... didn't made enough tests to be completly sure of this one.

Do lower control arm first.

Question always the same, if ball a bad ball joint is the cause of that clunk noise and those low speed vibrations, what's the most probable bad one ? The lower control arm one or the upper trust arm one ?

Again prying those ball joint when no load on the front of the car, they both seems OK, but noise coming front there and one of those is the culprit... but which one ? For sure changing both control arms amy solve the problem, but i will be better of replacing only the defective one.

Prying means nothing on a BMW... only way to tell if part is worn or not is to separate the ball joint and see if you can move the ball joint freely. Good ball joint will be quite tight to move and worn out one is easy to move

[632 Regal]

this will indicate if a balljoint is wasted not sway bar links. Sway bar links you need to be under the car and press the ends directly up and down to feel any play.

Bigger hole clunk can be 1 of 2 things, strut collar nut OR upper strut mount.

1) At low speed (forward and reverse) i jam the break, no clunk no nothing, so according to Jeff comment that should confirm that the sway bar links are good and not the clunk source. Running on gravel road with regular but small bumps there is no clinking neither, i need to pass on a goob pot hole or greater step to hear the clunk.

[Claude]

Prying means nothing on a BMW... only way to tell if part is worn or not is to separate the ball joint and see if you can move the ball joint freely. Good ball joint will be quite tight to move and worn out one is easy to move

So what is so different in the design of a BMW ball joint from others make (beside the fact that they are installed at the end of a steel arm) that they can't be check like others ?

For sure it's obvious when they are torn apart, but when it's not the case and the clunking noise come from there... we should be able to detect which one without having to change them all !

Again, to sum up:- sway bar end link bar OK (no loose at all)
- Tie rod end ball joint OK (no loose there neither)
- Trust collar nut can't be tighter
- clunking noise heard only when the wheel passes over a good step / bump or pot hole, otherwise nothing there
- sometime not always, when slightly breaking at low speed (below 40 km),
i feel a vibration on this right wheel and hear the clunking noise at the same time. Can't reproduce this vibration when i jab the breaks at high speed
- tires are good (would say half milage done) no abnormal wear sign.
- From outside the car, near this wheel, running over a 2x4 stud produce the clunking noise and it come from the center of the wheel (at steering plate level) not from the strut head level.