Clunking Noise/Suspension Refresh

[spidertri]

So whenever I go over bumps with someone sitting in the rear seat the driverside rear suspension will make a clunking noise. It only happens when there are people in the backseat. I am pretty sure that the previous owners never replaced any of the suspension parts and looking at the shocks they all seem to be leaking fluid. I really want to replace the shocks/springs with a bilstein sport/H&R sport combo but I am lacking money for that at the moment.

I figured that it would be a good idea to replace the old bushings with new and improved ones if possible. For the front suspension should I replace the whole control arm with a meyle unit? I have read that the stock ball joints don't go well with lowered suspensions. What control arm bushings would be best suited for daily driving duty, I have looked at the M3 ones but I am not sure what the difference is between the offset and non offset ones.

For the rear parts I have really only looked at the rear trailing arm bushings, I am guessing that the stock ones work fine? Looking at the diagram on realOEM it appears that we need 4 bushings? How hard are these to install? Can I do it or are special tools needed?

Are there any other bushings that I should look at replacing?

[spidertri]

Anyone? I have read several threads on this but I am just looking for a bit more info on these bushings.

[bullmand]

What you're describing is most likely the rear shock mount. You have to pull the carpet out of the sides of the hatch area to get to them, but it's easy to see if they're bad and they're easy to replace. The only other bushings in the rear suspension are the trailing arm bushings you mentioned, the rear subframe bushing, and the sway bar bushings. Start with the shock mount. It's easiest and could be cheapest depending on what you decide to replace it with.

[spidertri]

Do I have to remove the shock to replace the rear shock mount? I did pull the carpet away and tighten the shock mount to the appropriate amount, didn't help any. Is there an obvious way to tell if shock mounts are bad? Thanks for the help!

[mohaughn]

The rubber piece on the mount will be cracked and smooshed. If there is any play or wobbling in the mount, it is shot.

You can also get somebody else to drive the car, and you get into the backseat with the carpet out. Go over some bumps, and you should be able to the top of the shock moving on the mount if it is shot and causing the noise.

I would also say that if your shocks are leaking fluid, they probably should be replaced as well. You could just be bottoming out a shock.

[spidertri]

I will definitely go for a ride in the back seat and listen for the noise, if the mount is shot I suppose I would replace them with E46 M3 mounts.

I do need to replace the shocks and struts, I just don't have the money at the moment, but there's a good chance that it is just the shock bottoming out. Thanks for the help, I'll let you know if I figure out what's wrong.

[spidertri]

Finally had some time today to take a close look at the RSM. The rubber in the mount was not cracked or squished. (I attached a pic of it)

When I sat in the backseat and went for a ride there was no movement in the mounts other than the up and down motion of the shock. The noises coming from the shocks did not sound good, seeming to confirm that they are blown.

Any thoughts?

[bullmand]

That shock mount looks brand new. Given the other symptoms you've described it might be time for new shocks.

[spidertri]

Yeah, I noticed that it looked new as well, I guess the previous owner replaced them before trading it in.

The shocks are definitely not new though, I looked at them a bit more and its obvious that fluid has been leaking down the sides. Darn, guess I'll have to buy those bilsteins...

[spidertri]

Ok, so in the next couple months I should have enough money to properly refresh my suspension. I have started gathering a list of parts and would like your guys input on what else I need.

-Shocks/Struts - Bilstein Sports - BF.c (CMUZYY)
-Springs - H&R Sports - BF.c (CMUZYY)

Front End
-Control Arms w/ Ball joints - Meyle
-Control Arm bushings - 96+ M3 (Should I get new lollipops or reuse old ones?)
-Tie Rods - BavAuto (any good?)

Rear End
-RSM - Lifetime mounts from Bimmer World
-RSM Reinforcement plates - Bimmer World
-RTAB - Pelican (OEM ones, should I upgrade?)
-Rear Subframe Bushing - BavAuto


For anyone who has installed Bilsteins, what came with the front shocks? I have heard that bumpstops come with it. Should I get new front upper shock mounts?

Thanks for the help guys.