Rear clunking noise with brand new RSMs

[KnockOffBrand]

Hey all. So I replaced my blown rear shock mounts about 5 months ago with the ecs tuning rear shock mount kit. A clunking noise in the back of the car on the passenger side has started to develop in the last few weeks and I checked on the RSMs and they look to be fine. No wiggling or anything. Any idea what it could be? Thanks

[rcsoundn1]

sub frame mounts maybe

[indecline]

Rear shocks?

[KnockOffBrand]

I replaced all shocks, struts, and springs with h&r race and bilstein sports this summer

[KnockOffBrand]

The noise also seems to be coming only from one side. Could that still be subframe mounts?

[E30NJ]

Subframe bushings or trailing arm bushings could really be shot.

[Artful Dodger]

Im gonna ask some dumb questions.

-Is everything tight, like the bottom shock bolt, the RSM bolts to the body?
-Did you install the RSMs correctly? (My first time installing these parts, I put everything together in the floor, then removed my old equipment and installed the new. what I didnt know at the time, there are washers on the old stuff that you have to move to the new stuff)
-Are your lug bolts tight?

if all of this is correct, it is probably the trailing arm bushings, if they are the original rubber ones.

[jeffnhiscars]

I had a rear clunk after changing my suspension and it turned out to be a loose nut on one of the RSMs. FWIW I'd be surprised if a subframe bushing was worn enough to make noise without you having noticed sooner.