Cambo3

iTrader: (1)

I just lowered my 2000 ss about a month and a half ago. I noticed when I hit a bump on the passengers side the rear sound like a bad strut would, that bang/clunk sound. They are koni str struts and bent springs. Do you guys think my rear spring isolator has failed?

transamtom

iTrader: (8)

Have you checked your swaybar end link?

Corvett z07

iTrader: (2)

Does bent = BMR?

X2 for endlink, also check every bolt you've touched when you did the swap to make sure they're all tight

99Bluz28

iTrader: (35)

I'd check the exhaust right where it goes over the phb support for visible marks showing it's hitting the phb support. If it's hitting, then the passenger side rear exhaust rubber bushing is possibly worn out causing the exhaust to move when you hit a bump.
Or... if you have a aftermarket cat-back exhaust the over axle pipe probably need to be adjusted for better clearance from the passenger side axle tube since you lowered it.

Cambo3

iTrader: (1)

Bent does= bmr stupid auto correct

Cambo3

iTrader: (1)

No I have not checked the end links. How can I tell if they are bad? Where can I order the isolator for the exhaust on the passengers side? It is a little worn and could help give me more clearance.

Mongoose350

iTrader: (1)

I had something similar happen for awhile. Just recently found out that my rear passenger LCA wasn't even attached to the bushing anymore. It was broken pretty badly, I'm sure that was it. Do you notice any swaying or unexpected movement in the rear while driving? Check it out.

Cambo3

iTrader: (1)

I also have bmr lca relocation brackets and new lca. The car rides nice and straight, just when I hit a bump or I should say pot hole it makes the blown strut sound. I will have to look at my lca make sure they are tight and good.

transamtom

iTrader: (8)

The bolt usually breaks,pull your rear wheels and have a look.

Corvett z07

iTrader: (2)

Lol, not to say you're wrong or anything but a broken rear lower control arm, especially with rubber bushings, is almost non existent. You had some incredible luck there I have to say both bad and good luck for that matter.

The OEM endlinks have a narrow weak spot in the bolt that holds everything together. A weird design GM did... You can usually break it if the top nut is rusted on and you go to twist it off and the whole endlink goes *CHUNGGG*

Joeyofblades

iTrader: (2)

Could be a control arm. My Mustang had that issue. Among many other issues. But clunking stopped after old dirty control arms left and we put new ones in.

BMR Tech2

iTrader: (5)

This does sound more like a sway bar end link has failed. Be sure to check those and see if they are intact still as this is the usual culprit in these complaints.

Also just to cover all bases, double check the stud that comes through the floor for the upper shock mount and make sure it is completely tight. Any slack in that will cause the same issue you are describing

transamtom

iTrader: (8)

Ok OP what was it?