Hey everyone!
I have been prowling the forms for a few weeks now and this is my first post. It's truly awesome to have a place to check out issues and possible upgrades!! Thanks for this awesome community!

Now to my question,
I have a 2006 RX8 Grand Touring (GT) and I'm the 3rd owner...

I have been fixing small issues here and there (thanks to the forums!) and now I'm on to a new issue. It's bottoming out, or at least I think it is. When I hit a bump or go over a normal size road transition, the back of the vehicle makes a "bang" noise. No scratching, but as if the rear end hit the road.

I did not find any scratches under neath, and after looking at the shock coils - they appear good with no cracks or breaks and the struts look "new-ish"... They are oeSpectrum so I guess they have been changed not to long ago.

What would be some good ways to help me identify if I need to pick up new struts and install?

thnkx in advance!
-Fritts

 

Pull the struts and see if they're not actually BLOWN. We bought a new suspension from STANCE for my car because I got a deal on it, and one of them was blown from factory. Sucks, but you might have a blown strut. It sounds like it's doing the exact same thing my car was doing.

 

Tried that today, I could not get the bottom bolt to break free on the struts for the back.. Even with an impact... Guess I'll have to hit up a shop and see if they can try to break them free for me.

Gonna put a spacer on the coil till I can get in there and get them swapped out.

-Fritts

 

That does not bode well. I'm really going with blown struts.

 

Welcome,

When you get them out (try some PB blaster on the nuts). I think you will find nothing that looks like a rear bump stop. That is the banging sound. The rears go first, they are a different material. On one of mine, all that was left was a sliver that was packed around the base of the shaft.

If it were my car, I would order them ahead of time and have them ready. You can always return them. But, the bang is the top of the rear damper hitting the top of the black boot you can see from inside the trunk.

I chased this problem for quite some time.... Really pissed me off when I found out what it was.

 

Thnkx again everyone, I ordered new struts but I'm gonna have to wait a little longer to get some time off to attempt getting that bolt off. I did try liquid-wrench with no success.

 

New Struts without Bump Stops will make the same noise. The stops get used on this car. Think of them as the final level of a progressive spring. And, the stops are a lot cheaper than dampers.

 

quick update - the springs were worn out. Replaced and all is good!
ty everyone!

 

Springs? The odds are very high against the springs being bad, in my experience. The shocks are usually the first to go. They are gas pressurized, and when they lose pressure, the car will sag and bottom out. The bump stops also rot away over time (last about 10 years), as noted above. A typical OE coil spring is almost always good for hundreds of thousands of miles. (Some spring manufacturers offer a million mile warranty.)

Were they eBay springs or something?

 

I spent months trying to convince myself my struts weren't blown. By the time I got them out, they'd almost collapse under their own weight. Springs on the other hand look 100%, but I never bothered testing that theory.

 

I ordered the KYB Gas-a-Just shock/strut (2) from Autozone. We replaced the stops as well as my uncle told us it's possible they are ready to be replaced... So we spent a weekend and did the swap at my uncles shop. After the new struts were installed, we continued to hear the BANG sound when going over bumps. We checked all sorts of things after that but it continued. It got to the point that only 1 person could be in the car or it would do it just pulling onto the HWY.

I had a friend buy a few sets of springs for his RX8 and he asked me if I wanted a pair as he got 3 sets and only ordered 2. We took another weekend and put them on my RX8 and the banging stopped. The rear even sits much higher now than it did before. I don't have pictures of the OEM springs but I'll try to get some the next time I'm out at the uncle's house .

 

A whole weekend installing rear shocks?

But yeah the shocks and springs bother work together to determine ride height. Spring failure is very rare though but these cars are getting pretty old so it's possible.

 

Big guys, we had to wait for people with small hands to show up and help us.. LOL

lol, liquor/bbq - was more focused on that... The car was in the background.

 

Do you live in the rust belt or something? This still sounds highly unusual, unless there was an installation issue with the shocks or the like.

 

Nope, I'm in Arkansas. When it snows (even a trace of snow) we just shut-down the state.