I know there are a few threads one this but since I actually had success I figured I would post it alone.

My CPO 2018 Panamera 4S ST had a horrible shake at about 57-62mph as many report close to that speed. This wasn't a light shimmy in the wheel, the entire car shook.

Dealer told me it was wheel balance and after 2 trips never bothered to take the wheels off, just told me that is what it was even though the tires were brand new at CPO and they were supposed to balance them. They did not check them on a balancer.

Took it to another dealer for another issue because the original dealer was useless.

When I got the car 4 months ago it was dead quiet and even at idle. The shake existed driving. A month or so ago I've noticed a vibration at idle. It wasn't terrible and really only noticed sitting in my driveway idling.

Take it to the new dealer, they called me to tell me the left side motor mount was failed/failing. They replaced the motor mount, problem solved, zero shake, in fact the car is much better at all speeds.

So the motor mount seems to be the issue, either the dealer that CPO'd it missed it, or the shake appears before a failure was noticeable, not sure which.

It is possible that motor mount causes the issue before its visibly failing. It could be that it was on its way out, but not entirely failed. I drive a lot, probably more than most here. From purchase to today I've put 11K on the car in 3.5 months. Figure I felt the idle vibration 5,000 miles ago, so from possible starting to fail, to visual failure could be quite a long time for most owners based on how much they drive.

The only other change was taking the tires off/on, but improper torque should not be so specific speed wise.

I do not believe in reading all of the messages about this that anyone ever investigated or mentioned a motor mount problem, or finding a solution to solving the problem.

Hopefully this helps someone else.

 

Interesting. I hit a pothole and the car shook both on the road and at idle. I gave it to the dealer awaiting the 4 figure repair bill, but it was just a leaky motor mount covered under CPO. They said the leaking fluid was fresh so it wasnt like that for long.

 

Wait, motor mounts leak? Granted the last couple I replaced was on a '73 Duster

OP, congrats and thanks for the post. Fingers crossed that I don't follow you.

 

Most modern cars have fluid filled motor mounts.

 

I first learned about these liquid filled motor mounts early in the life of my 1983 944. The one on the exhaust side failed. Porsche came up with an aluminum shield that was easy to install. The vibration was most noticeable at idle. Urban cars suffered the most.

 

My PDK rough shifts are gone so it was the mount the whole time.

Dealer never did the PDK service for CPO even though they insisted they did. Another dealer confirmed and now surprise they are doing it tomorrow morning for me.

We just took it on a 1400 mile road trip this weekend and it was absolutely perfect. 3 months of annoyance because someone didn't do their job.