front end clunk

[jfoj]

More like 50-60 MPH stab the brakes, not hard but jump on them or stab them slightly. See what you feel in the steering wheel.

Also when backing up or maneuvering in a parking lot see what you feel through the steering wheel when stabbing the brakes.

Thrust arm bushing last 40k depending on the road conditions, then they get sloppy. By 80k they are UNHAPPY.

There is not a BMW on the road over 4 years old that is not a garage queen that could not use new thrust art bushings or better yet new thrust arms!

[Bayoux5]

The orange residue you see on the top of the shock tower is the remains of the pulverized upper guide support. It is a dense foam "doughnut" the sits between the support bearing flange (upper strut mount) and the large washer which is under the large nut on top of the shock piston rod.

I had this exact same issue and I first changed the tension strut (the front "control arm") with no change in the noise. I needed new tension arms so anyway so that was my first approach.

After changing the tension struts I ordered the parts to replace everything on the spring strut minus the shock and the actual spring. I reasoned that the shocks seemed to be fine.

I ordered the parts from GETBMW Parts as they were actually cheaper than the nearest competitor by price, BAVAUTO. I ordered the lower & upper spring seat, dust tube, additional shock absorber, upper and lower guide support, spring support flange (The most expensive part at $133), and new nuts and bolts for all fasteners that were loosened or removed. $254 total.

3 hours of my labor but I can probably do the other side in under two. I did one side thus far to track the changes. You'll need to jack up the offending side and then have a second jack to compress the suspension some to remove the spring strut assembly.

You can rent a spring compressor from Autozone or similar place. Spring compressor has to be set one rotation down or directly below the top end of the spring. Place the the other spring compressor 180 degrees from it.
Do not spin the piston rod nut without holding it in place by the hex inside the end of the rod. You can destroy an otherwise reusable shock.

After changing these parts that particular "clunk" sound was gone and the car was much quieter.

Good luck and follow all manufacturers directions on jacking, supporting the car and compressing the springs.

[Basem3]

Thanks for the time to reply and sharing your experiance. That sounds exactly what it is. Do you think that the spring support flange is a "must replace" part? From the pictures it looks like only a large shim of some sort. Does it have a bearing like the traditional upper strut mount has that may wear?

[Bayoux5]

The support bearing flange (BMW's words, not mine) in my opinion is an over priced part. It consists of an aluminum "cup" with three studs sticking out of the top and a small rubber, metal sleeved, bushing in the center. I could not find just the rubber bushing as a separate part. This bushing centers the piston rod like any other suspension bushing works.

Mine was cracked along with the bearing guides being totally destroyed/flattened.
So, I went ahead and replaced it. BAVAUTO offers a "Rhine" brand for $70. I went with the BMW OEM flange because I could not find any information on the Rhine brand longevity. I may change the other side with the Rhine part for comparison. Its all in how long that rubber piece holds together. I don't think the clunk was because of the bushing being torn so much as the guide supports (the foam pieces) being totally gone that allowed the shock to "bounce" against the top of the shock tower. The torn bushing would probably allow the strut to move off center which could shorten the life over time.

When I do the other side I will not order the dust boot as the original was dirty but appeared no worse than the new one. If you have to order parts before you take it apart you may want to get it in case its in bad shape. About $22 if I recall so really not worth not replacing it.

Do plan on replacing the rear control arm nut, the shock nut (large single one), the bearing flange nuts, the shock mount "pinch" bolt, the upper "wishbone" pinch bolt and nut (mine totally flattened the threads apron removal) and possibly replacing the sway links since you're "already there" and have to reeve one side anyway. You don't need to drop the sway link, just the upper side and swing it out the way. No need to drop the splash panel under the engine.

You will have to remove the plastic (probably broken and cracked) pieces on the cowl below the wipers. This is very easy and not worth explaining here other than you need a 13mm wrench to turn the plastic nuts holding them in place. 10mm to remove the lower pieces after that then your done in the engine bay for now.

Also pay attention to the orientation of the prop shaft as it has to in a certain position in order to pull the entire spindle down to get the strut out from under the wheel well. You can do it by feel but it helps if you look at the diagram ahead of time. Also loosen the hex screws holding the sensor wires and brake line so you don't put too much stress on wither as you pull down on the spindle.

This is 4-5 out of ten in ease if you're used to DIY. The sway link would be a 1 for whatever thats worth. From the time the strut is in your hand to putting it back on the car should take no more than 30 mins. The rest of the time is getting to it and buttoning it all back up. The second one will take half the time.

And FYI, I used my Makita 18V impact to compress the spring and it worked perfectly. Much faster than by hand with a ratchet. The detailed instructions for all this are available on this site. Just do a search. I never could get the exact torque values. So far now I used 20 years of wrenching experience to determine how tight. I erred on the low side and when I get the actual numbers this week I'll check all the fasteners again. I am not driving the car daily in the meantime for no other reason than I don't have to.

Good Luck! I am half asleep so forgive the rambling sentence structure...

If someone reading this can provide the torque values it would be much appreciated:

31 12 2AZ (I get the 31 12 part...)
31 12 6AZ
31 12 7AZ
31 12 8AZ

I used 56N*m for the 6AZ (If I recall, I wrote it down somewhere) which should be about 40 Ft*lbs. and scaled from there. But, I may be thinking of some other bolt...Nevermind.

[Basem3]

Thanks again and your not rambling just providing critical info! I'll probably go with the Lemfoerder brand bearing mounts if I can find them. I think they are a OEM supplier and about 1/2 price. Unfortunately others have the same idea and all the suppliers I've seen carry them are sold out.
I've done this job on several BMW's including a e30, e39, and e90 but no FWD.
I've found one of the most difficult parts was trying to remove the strut Assy. from the wheel well, not enough clearance. Can you turn the prop shaft by hand to align it properly while the car is in the air?

[Bayoux5]

Yes, all by hand.

As you pull down on the spindle you can turn the shaft until it slides out. The written details show how to orient the shaft based on the flat sections. They have to be straight up. It will be obvious when you see it. Pay attention to not excessively pull on the shaft and stretch the CV and rack boots too much.

Also be cautious to not damage the CV boot as you wiggle the strut mount around to get it out. You get very close to the boot at times.

Note the direction and orientation of the upper spring perch with respect to the direction of (vehicle) travel. This is spelled out in the worship documents (again, search this site for them).

When you go to put it back in (the prop shaft) you may have ti turn it whilst pushing it in. When it aligns properly it will slide into place. Again, it will be obvious when the splines align as it will suddenly move in towards the engine.

When you put the spring strut back on the car secure it at the top with one of the flange nuts. Tighten the nut by hand only a few turns. This allows the strut to be supported from above but also allows leaves enough play in it to align the other parts. Once you get everything started you can begin tightening the fasteners.
I used a strap to secure the wheel hub (spindle) to the upper wishbone while I worked on the strut on the bench. Don't just let it hang by the boots.

I forgot to mention that you should also consider replacing the upper and lower spring perches.

Look at the REALOEMBMW site for the exploded view of everything you need.
RealOEM.com - Online BMW Parts Catalog

[Basem3]

Good deal thanks again.

[torqueisking]

Originally Posted by ard

I will just say that Thrust bushings CANNOT BE DIAGNOSED BASED ON VISUAL. They look fine 40k after they are shot. This from the E39 world. (Were we use X5 bushes as an 'upgrade' into the E39 lower control arm)

One question- at 50-60mph and light braking, what do you feel????

Well noted...thanks. Changing thrust bushings next if the new sway bar links I just bought do not solve the issue.

No issues at 50-60mph or any other speed and light or hard braking.

[Basem3]

Originally Posted by Bayoux5

Yes, all by hand.

As you pull down on the spindle you can turn the shaft until it slides out. The written details show how to orient the shaft based on the flat sections. They have to be straight up. It will be obvious when you see it. Pay attention to not excessively pull on the shaft and stretch the CV and rack boots too much.

Also be cautious to not damage the CV boot as you wiggle the strut mount around to get it out. You get very close to the boot at times.

Note the direction and orientation of the upper spring perch with respect to the direction of (vehicle) travel. This is spelled out in the worship documents (again, search this site for them).

When you go to put it back in (the prop shaft) you may have ti turn it whilst pushing it in. When it aligns properly it will slide into place. Again, it will be obvious when the splines align as it will suddenly move in towards the engine.

When you put the spring strut back on the car secure it at the top with one of the flange nuts. Tighten the nut by hand only a few turns. This allows the strut to be supported from above but also allows leaves enough play in it to align the other parts. Once you get everything started you can begin tightening the fasteners.
I used a strap to secure the wheel hub (spindle) to the upper wishbone while I worked on the strut on the bench. Don't just let it hang by the boots.

I forgot to mention that you should also consider replacing the upper and lower spring perches.

Look at the REALOEMBMW site for the exploded view of everything you need.
RealOEM.com - Online BMW Parts Catalog

I lucked out on this one. Purchased it from the local Lexus dealer who gave a 90 day 3k warranty. Even though the warranty stated drive train parts only, they agreed to do the repair on both sides! Had 700 miles left to go on the warranty Got to put in a good word for Brumos Lexus

[Bayoux5]

That's good news. Not a hard repair but always easier when someone else does it, and for free.

Make sure they replace the guides, the flange and install a new shock bumper at the least.

Report back and let us know how it feels when the work is completed. That way we can confirm the diagnosis and help someone else in the future with this issue.