I had my KYB AGX installed by my Nissan dealer last week. Ordered them from Cattman.

There is a rather loud noise that comes from the back frequently. The noise sounds like knocking on a large sheet of metal (with resonance), or like kicking on a metal trash can.

I know that the stiffer shocks transmit more energy to the body, resulting with more noise, but my setting is not that hard (AGX set to minimum, 15 inch tires inflated to 32 psi) and the noise sometimes happens on relatively small bumps. The noise seems much exagerated compared to the increase in stiffness.

Has someone experimented something similar when stiffening suspension? Can RSTB solve that problem? Any idea?

By the way, the AGX help handling significantly. Floatiness has gone and the car feels much crisper and tighter, with better steering feel. On the other hand, ride is harsher on rough roads and new noises and squeaks have appeared.

 

Did you use OEM dust covers or AGX dust covers for the rear? could be that your car is hitting the bump stop. Did you get lowering springs too?

KEvin

 

I have the stock dust boots, stock springs and stock mounts.
My only mods so far are a FSTB and the AGX. I have a RSB ordered.

 

Hmm....metal sound with resonance huh?? Does it occur only on bumps? is it specific or does it hapen randomly? I'm not sure about that one, don't think I've heard of that. Might want to ask njmaxseltd, he's the suspension guru.

 

ok, i think i know where the noise is coming from. Refer to my post

http://forums.maxima.org/showthread.php?threadid=135832

 

The noise is not like a metallic impact (metal to metal) but rather like the resonance that occurs on a large sheet of metal after being hit by a hand or a rubber mallet.

It happens when hitting bumps, not necessarily large or harsh ones. I haven't figured exact characteristics yet.

 

Also be sure that the center piston nuts are tightened to spec. The shocks generate a lot of noise when loose. Kinda sounds like metal to metal banging.

 

Odd....

Besides the obvious retorqueing of all the strut bolts and making sure the springs are still seated correctly....

Maybe your spare is loose and the extra bounce you're getting now is moving it around more?

-RMB

 

When I first changed mine, I had a similar noise. I traced it to the hard plastic trunk liner on the sides that go over the sheat metal. Those need to be peeled back to access the top of the strut and if the clips are broken or the pieces are put back wrong, they whack the metal portions of the structure making a metallic sound that is really annoying.

 

Check your trunk latch. I thought the noise was coming from suspension too but I eventually figured out it was coming from the lid of the trunk. Quick way to check is just go to the outside of your car and jiggle the lid a bit from the top. If it is, you can adjust the height of the latch.