JRZ RS Pro rear driver side noise

[c90369739]

The JRZ RS Pro I got came with rear shocks inverted, and the inverted rear shocks also come with both the top and the bottom mounts as shown.

JRZ RS Pro is excellent, both on the street and the back road... Just a small drawback that there a noise coming from both side of the rear, especially the driver side, and I have scheduled to:
1. Replace the bearings dealer provided as warranty parts.
2. Replace the one-time use bolts that I didn't change out for the last three suspension works.

However, both the bearings and the bolts don't make any noise when I shake the tires while vehicle is lifted. Therefore, I started to look into another possibilities, and one thing I noticed is the shock is not exactly vertical when being looked at from the side of the car, it goes a bit toward the front when going downward. I put on a ZIP tie, which mitigated the noise a little bit, might be my wrong judgement. Therefore, I started to think my IRS might not aligned. I already the IRS alignment kit, and I wonder if I can still correct the IRS? Or how can I fix this problem.
I assume the shock should be vertical with the IRS in a side view?

Any input is welcomed, and I will write up a review, both with the installation and driving , once I have my first track day this April.

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[VictorH]

I have run the RS-Pro in another vehicle for the last 20,000 miles it's a fantastic set up and amazing on the track. It's a robust set up. Firstly, I think it's highly unlikely the shock is the source of your noise. I don't own a Mustang yet ( I have one on order), so I don't know the specifics of the rear suspension. Firstly, I know this from experience too, you won't find the source by trying to push on the suspension by hand, you just can't generate enough suspension movement.
First look at anything that was loosened or changed, make sure it's all tight. On some cars the sway bar drop links can get loose and make noise. The shock mounts have no gap or play in the shock link or to the body? Sometimes what I've done is one at a time disconnect a component and drive the neighborhood to see if that eliminates the noise, though you're limited to drop links and shocks themselves. Did you change the springs? I've seen coil bind cause noise on full compression over speed bumps and such or if on rebound there's a little gap between the coil and the spring perch that will give you a tapping noise too. Anyway, that's a few things to check. Good luck. Lastly, no chance you let all the nitrogen out of the rear shocks for some reason and didn't refill? That would be really bad if left too long, but they come fully charged. Don't check the pressure unless you have Nitrogen refill rig. Good luck, it will work out and then you'll enjoy an amazing system.

 

[Brian@BMVK]

What kind of noise?

 

[Radiation Joe]

I also have the alignment dowels for the rear subframe. I've suspected they might be the source of some low speed rattles I get from the rear end. They're coming out in a few weeks. I'll see if the noise goes away after that.

 

[c90369739]

I also have the alignment dowels for the rear subframe. I've suspected they might be the source of some low speed rattles I get from the rear end. They're coming out in a few weeks. I'll see if the noise goes away after that.

Please keep me posted.

 

[c90369739]

I've seen coil bind cause noise on full compression over speed bumps and such or if on rebound there's a little gap between the coil and the spring perch that will give you a tapping noise too.

Another forum member, db252, who has the JRZ RS also suggested it is the coil bind. I am going to grease the coil with anti seize and see how it goes before I make any change to the shocks. I set the nitrogen pressure to 150psi, the lowest suggested pressure, for street, will it cause any issue if it is slightly below 150psi?

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