Clunking in rear over hard bumps

[Jand3rson]

Just wondering if anyone has any ideas about this, in the last few weeks or so, I've noticed a mild clunking coming from (what sounds like) the rear when I go over any hard bumps or cracks in the road. My RSMs are brand new, just installed a few weeks ago, and other than that, there's been no changes made to the rear suspension. Shocks on the car are only about a year and a half old, IE3 springs. I jacked up the car and just took a quick look (it's getting dark and my garage lights suck), and didn't see anything out of the ordinary. Shock mounts seem tight and nothing has any play anywhere. I was thinking I might go in there tomorrow and just make sure everything is tight all the way. The only thing I did notice is that when I push up and down on the rear to bounce the car, when I do it really hard, I can kind of hear it faintly. Anyone have any ideas?

[backtrail69]

Might be worn subframe bushings. Do you still have spring pads in? Both my cars clunk a little bit over rough roads. Just make sure everything is tight and you should be good to go. I want to see that eta sport at the picnic!

[FoxXx325echo]

when you pushed on the car did it make the noise coming down or going up? check your endlinks and rear sway bar mounts...another thing, check for rear end clearance with the exhaust...just a couple guesses, but its not uncommon stuff to see with fresh suspension work that settles

[Jand3rson]

Might be worn subframe bushings. Do you still have spring pads in? Both my cars clunk a little bit over rough roads. Just make sure everything is tight and you should be good to go. I want to see that eta sport at the picnic!

I'll bet you that's probably it. Those are the next round of bushings I need to replace, the rear subframe and trailing arms. I wonder if going to the new, stiffer RSMs made a pre-existing noise just that much more noticeable.

[xLibelle]

even if the subframe mounts were torn, they wont clunk. that is unless maybe you completely unload a rear corner in a turn, etc.

theres this function around here called search. did you use it josh? ;)
its your shock mounts. the rubber condition can be deceptive

[Jand3rson]

its your shock mounts. the rubber condition can be deceptive

I don't think so. They're brand new from Bimmerworld.

[xLibelle]

are they OE or some kinda aftermarket?

if they bolted in easily, they still could be too lose. we are talking about a point in the body that is known to ripped from the shocks force. measly rubbers will give pretty easily.

but its just a suggestion. ive seen this be the case personally, a few times now. thats all

[Jand3rson]

are they OE or some kinda aftermarket?

if they bolted in easily, they still could be too lose. we are talking about a point in the body that is known to ripped from the shocks force. measly rubbers will give pretty easily.

but its just a suggestion. ive seen this be the case personally, a few times now. thats all

They're an aftermarket unit, Lifetime RSMs from Bimmerworld.



I'm going to check them, but I can't imagine them being the problem. I will look into it, though.

[xLibelle]

ok, thx for the pic.
what is on the underside, more rubber? if not, theres the problem. but in anycase, i would tighten the nut on the shock down until the rubber bulged a little.

[Jand3rson]

ok, thx for the pic.
what is on the underside, more rubber? if not, theres the problem. but in anycase, i would tighten the nut on the shock down until the rubber bulged a little.

Yeah, thre's another of that same black rubber bushing on the underside.

[Mr Deagle]

is the shock mount on the TRAILING arm tight?

Its a 19mm wrench, check it out


Im saying that from experience

[Jand3rson]

I'll go ahead and assume you meant the trailing arm, but yes, I'll check that too.

[Mr Deagle]

I'll go ahead and assume you meant the trailing arm, but yes, I'll check that oo.

Yah sorry about that, its late TRAILING ARM

[BigFurryWhale]

even if the subframe mounts were torn, they wont clunk. that is unless maybe you completely unload a rear corner in a turn, etc.

theres this function around here called search. did you use it josh? ;)
its your shock mounts. the rubber condition can be deceptive

Is this true that worn subframes won't cause clunking?

Will sway bar mounts cause clunking? I think mine might be on the way out.

[Mike325]

Worn rear suframe and sway mounts will cause clunking, I am not sure what he was talking about. Clunking is the most common problem people have with bad RSB.

Josh, over hard bumps only? Is your battery tied down sir?