You didn't say the sound was when done I thought that was when trying to move.

Quite recent thread was the case of CV coming out of the differential. It will be quite obvious under the car if a CV is detached (or broken etc).

lift one end of the cat at a time, turn the wheel by hand, if the diff is working and the drive shaft is held by the park prawl, the opposite wheel will turn the opposite direction.

If you get a freewheeling wheel you have a defect in the CV or dif usually. You can look for drive shaft motion also, You should not be able to turn either drive shaft when In park.

You can put the car up off the ground then put the car in N and see if you can turn each drive shaft by hand to see if any wheel fails to turn. Better to do these tests power off.

Usually if the CV pops out, you'll get a grinding sound of the spline trying to engage when in gear (the rubber boots will usually add just enough pressure).

I have a good feeling that you are looking at a relatively inexpensive fix now that I know the sound was likely from parking prawl. A broken or detached CV or dif will give you all the symptoms save this: park will not work properly: you can push the car if a CV is broken, though it's possible one axle might lock if the other doesn't

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)