i have a 1997 park avenue ultra with 80 k miles on it (supercharged)
the car makes a deep noise but its not too loud. sometimes it gets louder when i switch from neutral in drive
i got the original drivebelt on it , i bought the 2 belts new and all the idler pulleys and replace them soon ,but i don´t think that noise come from a belt
anyone knows what it is ? the supercharger coupler maybe ?or the transmission?
thanks a lot
HERE IS A VIDEO mp4: 20191108_174244_1.mp4

 

Sounds as if supercharger is running dry, bearings, is it getting oil? Remove serpentine and check all devices for side play in sheaves, a bit of in and out play is OK if any on components. Idlers were changed, don’t think it’s tranny but check fluid while at it......