[Ocharlas]

For the past few months, I've had a knocking/rattling noise coming from the front of the car, and in the past couple weeks it has gotten worse. It happens when I'm going slow(ish). It happens over humps. It happens in the wet, in the dry, in the hot, in the cold, after bumps.

In short, it's the same knock that so many other people on this forum have described. I've taken the liberty of doing many of the things I saw posted: it's got new shocks all around (I just double checked the strut mounts and they are tight). It's got new tie rod ends, sway bar bushings, sway bar end links - the old ones were in fact shot - new motor mounts, aaaand...the rattle still there. Everything down there feels tight, and I don't want to keep throwing parts at it until I'm living out on the street with a still clunky BMW. Every time I've taken it somewhere the mechanic says "everything looks good up front."

Any ideas? Control arms? Tension strut? I don't know what else is under there...
Thanks!

[Wolf 335]

If all parts are new then there is one component that is not torqued properly.

Check those sway bar links where they attach to the strut. It's very easy to have that nut not on properly when installing the struts. If you don't lift the wheel carriage to ride height, there is possibility of applying the nut on link arm at an angle. It will give you a feel that it is torqued all the way, but when you lower the car the angle will change and you will have a loose connection.

Also check your stabilizer bar connecting points under the hood.

[SE7EN335]

Originally Posted by Ocharlas

For the past few months, I've had a knocking/rattling noise coming from the front of the car, and in the past couple weeks it has gotten worse. It happens when I'm going slow(ish). It happens over humps. It happens in the wet, in the dry, in the hot, in the cold, after humps.

In short, it's the same knock that so many other people on this forum have described. I've taken the liberty of doing many of the things I saw posted: it's got new shocks all around (I just double checked the strut mounts and they are tight). It's got new tie rod ends, sway bar bushings, sway bar end links - the old ones were in fact shot - new motor mounts, aaaand...the rattle still there. Everything down there feels tight, and I don't want to keep throwing parts at it until I'm living out on the street with a still clunky BMW. Every time I've taken it somewhere the mechanic says "everything looks good up front."

Any ideas? Control arms? Tension strut? I don't know what else is under there...
Thanks!

Check control arm bushings, sway bar end links, steering shaft u joint (YES this stupid thing had a lot of play in mine and made my steering wheel bump when going over bumps and make the steering sticky and not self center)

[Ocharlas]

Ok I just put the car up with the shock under load and played around with all the stuff down there. The sway bar end links seem really tight, no give at all. Control arm has no play that I can tell. I haven't checked the steering shaft U joint, I'll do that in a minute, but the steering feels normal and about as centered as it's ever been. Also I don't really feel it through the wheel at all, it just seems to emanate from under the car.

The only thing that I could get a tiny bit of wiggle on was that tension strut (is that also called upper control arm? I'd never heard that term until now), but it's not like when I replaced the end links, we're talking maybe 1-2 millimeters of play here. Is that normal? Or shot?

[mike-y]

check the big strut shaft nut under the diagonal strut brace. Not the mounting nuts. it's common when the strut shaft isn't completely settled when you install the shock, so you tighten it down. After a few days of driving, the shaft loosens up and will move up and down within the strut mount.

if you jack up the car, the shock extends and hides the problem, you have to tighten the nut with the springs compressed under the weight of the car.

[chris@strutmonkey]

I agree that this is a good thing to check, although it does not matter if it is under load or not. Torque to 46ft/lbs.

Originally Posted by mike-y

check the big strut shaft nut under the diagonal strut brace. Not the mounting nuts. it's common when the strut shaft isn't completely settled when you install the shock, so you tighten it down. After a few days of driving, the shaft loosens up and will move up and down within the strut mount.

if you jack up the car, the shock extends and hides the problem, you have to tighten the nut with the springs compressed under the weight of the car.

[Ocharlas]

Ah! Smart I didn't think of that. Will check that tonight as well.