Rear Suspension Knock

[cham]

I’ve got a 2016.5 CX5 GT with an interesting knocking/rattling when going over bumps. The sound is specifically coming from the driver side - rear and only makes noise when that driver side - rear wheel hits a large enough bump or undulation. I have already narrowed it down to the driver-side rear, and secured anything in the trunk that could be making this sound.

Below is a video of what it sounds like. I see there are a few TSBs relating to the rear suspension. Rear coils can snap, rear shock top mounts can snap, and rear differential bushings can fail prematurely. My money was on the shock top mounts but it visually checks out. Grabbed sway bar link and I could not move it with my hand at all.

Can it likely still be the top mount of the shock even if it visually checks out? Are loose rear shock mounting bolts common? The Original shocks are still on the car and to my knowledge have never been removed or serviced. Any ideas or experience?

 

[Snake]

I wasn't clear on whether or not you checked the shock mounts bolts for looseness? That's the first thing I'd check. An upper mount came loose on a Honda we once had and the rattling was horrible.

 

[cham]

Yeah I’ll get torque specs and double check the mounting bolts haven’t loosened. What is the best way to diagnose sway bar end links?

 

[GFrosty]

What is the best way to diagnose sway bar end links?

This might help.

From the 2014 workshop manual:

Front Stabilizer Control Link Inspection

1. Remove the front stabilizer control link. (See FRONT STABILIZER REMOVAL/INSTALLATION.)
2. Inspect for bending or damage. If there is any malfunction, replace the front stabilizer control link.
3. Rotate the front stabilizer control link ball joint stud 10 times and shake it side to side 10 times.
4. Measure the front stabilizer control link ball joint rotational torque using an Allen wrench and a torque wrench.

• Front stabilizer control link ball joint starting torque: 0.8—3.5 N·m {8.2—35 kgf·cm, 7.1—30 in·lbf}
• If not within the specification, replace the front stabilizer control link.
• Even if within specification, if there is excessive play in the front stabilizer control link ball joint, replace the front stabilizer control link.