[QUOTE=jzchen;4896504]​​​​​​
I notice with the 20" wheel option the upper control arm bushings last about 50k mi. (It does not matter air or coil suspension). Then at high speed the car feels horrible (even just one side as the other side was replaced about 1 1/2 year prior).

Very likely the upper control arms need replacing. I replaced the air strut at the same time with an Arnott unit because I already had to remove the strut to get to the upper arm. Try those first....

I have an appointment in March for service I would do it and keep you posted. Thanks for the information. Meanwhile if your got fixed
let me know too.
Thanks

 

Mine also makes the crunch sound when cold. I have heard that the swaybar bushings can also be the cause of the squeak so I'll be digging in to those this weekend.

 

I haven't dealt with any other bushing/suspension piece replacement than the upper control arms and air struts as of maybe 52.5k mi, current odometer. After alignment car drove great again. (Yes it appeared to solve the freeway instability. I don't think my wife even noticed, but I could definitely feel it. I got acquainted with the early-ish failure of the upper arms from the shop when they helped me repair a leaking passenger side air strut. The tech showed me exactly what to look for moving the arm asking the same crunching question I now share with you.... The arm moved to a new position easily, and stayed at the new position. Upon installation a new arm firmly stays in the place you torque it at. This I learned when I replaced the driver side on my own). I dreaded two parts of the job, and spent a lot of time trying to align the wiper arms nicely upon reinstall. (Unless I'm confusing with the HPFP replacement that I did). Popping the ball joints out, one on the upper arm, and one on the lower suspension, scared I was going to lose a limb or get injured. For the lower one I placed a cushion underneath and just let the tool fall down onto it when it finally popped loose. For the upper one I held the bottom arm of the tool with silicone oven mitt hoping to cushion the recoil. (I didn't feel any and glad nothing hit me). Thankfully no fingers lost/no injury....

I do note two things, the crunching seems to be coming back in the cold. (Sound is localized to the upper part of the engine bay so I suspect the upper control arms again, although my choice of Duralast on the driver side is questionable, I wonder what the shop used on the passenger side as they supposedly use original Porsche parts). The lower arms at least can be removed easier/without strut removal but I haven't dealt with them nor the sway bar bushings I confess...

 

Some on here have replaced the upper arm bushings with more durable polyurethane. I know one user made his own and may be able to produce them for you for a reasonable fee. Argh, trying to remember his user name off the top of my head, my memory is not so good anymore.) I ended up replacing the entire arm because I wasn't sure how long the ball joint would last. I did send a suggestion/request to Super Pro in Australia in the hopes they would come out with a replacement upper arm with polyurethane parts.

I kept the old arm. I'll try to take pictures in daylight....

 

There is a visible crack parallel to the metal along the edge on the sides with the part # listed. I noticed a slight chip in the part number side I suspect damaged in storage.

These bushings I suspect are subject to a lot of torture during driving....
https://drive.google.com/drive/folde...Ai2GzjY7l6_yiC

 

I read that thread too - https://www.6speedonline.com/forums/...eplaced-2.html
The guy with the custom bushings is @negb but I don't think he can make them for others. There is also a link in the thread to some "Siberian Bushings" but I can't find them made for a Panamera. Maybe the Cayenne bushings or another model would fit if you emailed them...

 

IIRC, our forum member @Dogwood has also developed more durable bushings - hopefully he'll chime in if he can help

 

Bingo thanks! @DogWood

He and another forum member worked on theirs together in this thread. This specific post has an image of his bushing:

https://www.6speedonline.com/forums/...ml#post4835919

Siberian Bushings also makes one that is for a Cayenne but they also specify it for the Panamera upper arms. Also PowerFlex (in GB?)...