help me track down a suspension rattle

[Ohsoslow]

Would be great if you could put up some videos of the driveshaft play, ideally before and after.. I’ve got what I think it massive driveshaft play, so would be good to know if it is normal or not.. and If its the potential cause of a clunk I’ve got going on.

[LightlyToasted]

Originally Posted by Ohsoslow

Would be great if you could put up some videos of the driveshaft play, ideally before and after.. I’ve got what I think it massive driveshaft play, so would be good to know if it is normal or not.. and If its the potential cause of a clunk I’ve got going on.

Got the part today. Hope to be able to install it tomorrow. Will take some videos along the way.

[josiahg52]

I don't know what years but some driveshafts were recalled for premature u-joint failure.

[Ohsoslow]

Yeah, I emailed bmw, and mine isn’t on the recall list, But it has me a bit concerned! I got under the car and just took a video (found a friggin oil leak too..) but I have no idea how to upload it.. I could email it though..

Mine doesn’t appear to be the u joints, more the yoke that goes into the transfer case, heap of movement!

[LightlyToasted]

Originally Posted by Ohsoslow

Mine doesn’t appear to be the u joints, more the yoke that goes into the transfer case, heap of movement!

Mine also. I'm not sure if the culprit is the u-joint or the connection to the transfer case, but the TIS diagnosis procedure seems to blame the u-joint / drive shaft if there is play.

[LightlyToasted]

Well, I got the front drive shaft replaced. That was a brutal job. It's easy enough to unbolt the drive shaft from the front diff, but a frame cross member prevents you from dropping the front of the shaft so that it can be pulled out from the transfer case. I made a tiny bit of extra room by unbolting one exhaust mount to allow the pipe to be moved a slight bit, and devised a hard-to-explain scheme to work the front u-joint under and behind the guibo so that there was enough room to pull the shaft from the transfer case. Installation of the new one by the reverse process was even harder.


And it did not fix the clunk


The u-joints on the new shaft were smooth and somewhat stiff as you'd expect. The u-joints on the old one were floppy, but didn't really have any notchiness or lack of smoothness. The up/down lateral play was significantly reduced, but not eliminated. I think that play is in the transfer case. Any radial play seems like (normal?) gear lash at the front diff or transfer case - if you hold the guibo steady like the TIS suggests there's no radial play.



I apologize but I was not able to take any video. I couldn't get my camera and tripod under the car, and I had a time limit.


Not sure where to go from here. I'll maybe compare the brake pad play to the other side, but I'm basically out of ideas.

[SeanC]

1. Did you rebuild the strut yourself? If so, did you make sure that the correct stud bolt was flush with the positioning pin that goes into the spring holder groove?

2. Did you inspect the functioning of the brake caliper? Is it completely free of rust, free to move, and the boot is intact?

[LightlyToasted]

Originally Posted by SeanC

1. Did you rebuild the strut yourself? If so, did you make sure that the correct stud bolt was flush with the positioning pin that goes into the spring holder groove?

Yes, I rebuilt the strut myself. There was no locating stud on either the OE shock nor the KYB replacement, nor the Bilstein replacement, IIRC. Yes, that's right - I've actually rebuilt it twice trying to find this rattle. The OE and KYB have a convex bottom which matches the profile of the strut holder, whereas the Bilstein does not. There's no movement of the shock in the strut holder.

Originally Posted by SeanC

2. Did you inspect the functioning of the brake caliper? Is it completely free of rust, free to move, and the boot is intact?

Yes, yes, yes, and yes. There is a very minor amount of play between the pads and the caliper carrier which I'm going to compare to the other side, and maybe swap pads from side to side. I replaced the pads about a year ago with Pagid black pads; a little dusty but certainly good quality. I always wire brush and clean the caliper carrier contact points when I change pads.


Now that I've been driving the vehicle for about a week after replacing the front drive shaft, it seems like the clunk and rattle are reduced by about 50%, but it's really hard to tell as the roads are clearing of snow and aren't quite as rough.

[Badsmerf]

Any more parts changed or troubleshooting?

[ard]

I keep seeing this thread pop up....



SOOO excited, I think "Oooh, gonna hear what it turned out to be".




and no luck.