E53 knock sound
 

Hi guys,
I would appreciate any help please:
Driving the other night with only lights on (no heater or A/C) - parked it, get a knocking, sound. Turn off, turn on, lights clear.

I would check for trouble codes first though it sounds like transmission or associated issue. I would have an independent transmission shop do a thorough diagnosis. To be sure I didn't make the problem worse I would have it taken to the shop on a flatbed.

It could be transfer case or worn out gear in drive shaft.

I agree that it sounds like a transfer box/worn propshaft spline issue.

The noise you hear when you put it in Park is the park pawl ratcheting on the park lock gear because the output shaft is rotating. You should be able to tell because the park lock won’t hold the vehicle.

Phil

Take the harness connector at the transmission apart and check for corroded pins or contamination in the sockets. Clean thoroughly with electrical contact cleaner, coat with dielectric grease and reassemble. Reset codes and test vehicle.


2002 X5 3.0 344,000 miles
2014 428i 39,000 miles


2004 325i sold at 123,600 miles
2001 325i sold at 66,000 miles


1970 Firebird Under restoration