Edit: Videos all here: https://www.youtube.com/channel/UCkZ...JSJ8-KJOBXqLGQ
Another noise identification exercise. Pardon the lengthy timeline, but hopefully it’s helpful in diagnosing. A few months ago ZHPizza found a loose nut on the top of one of my front shocks. An impact wrench tightened this up ~1/4 of a turn. Not the perfect solution as you can’t counter hold with an allen key, but it completely eliminated a very annoying noise from the front end. Good day.
Over the long new year’s weekend I double-checked the 3 nuts on the top of each rear shock in the trunk b/c I was curious. The two outer nuts are 10ft/lbs….and the central nut on the shock is 17 ft/lbs. All these felt tight. Took the car out for a long drive on Monday and there were no noises.
It got very cold Monday night – coldest it’s been yet this year – and Tuesday morning driving to work I heard some pretty loud cracks (maybe better described as one 2x4 board being slapped against another) coming from the back end. My parking garage ramp has some ripples in it (for lack of a better word) that get the shocks oscillating, which used to always create the noise I hated on the front end that ZHPizza fixed. This time, I got a really loud vibration from the back end. I do have this on video with good audio, but need to create a youtube account to upload. This vibration sound was basically the 2x4 cracks in very quick succession.
Tuesday night I re-tighten all the nuts on the top of the rear shocks again. Probably tightened them a bit beyond spec but not materially so. The noise has gone away on the parking ramp, however it still is there on certain types of surfaces. Single bumps (i.e. a speedbump) don’t reliably produce the noise, but generally rough roads (where the shock is oscillating) can occasionally.
I’m totally mystified by this. If I had mistakenly loosened the nuts over the weekend rather than confirming that they were tight, that would have been apparent on Monday. The problem only became evident once it got cold on Tuesday. And having re-tightened everything Tuesday night, the problem has largely gone away but there are still certain road surfaces that can produce the noise. Given the very modest torque specs for the 3 nuts in question, I have trouble believing these were ever loose.
These are the shock mounts that I have: https://www.ecstuning.com/b-jt-desig...SABEgIWgfD_BwE