Possibly there are some bronze bushings or bearings inside the engine.
Somebody on here should know for sure.
Yesterday I learned the 04 Impala sitting next to the parts dept at my
dealer is waiting on a NEW transmission. Its a 6 month old rental car.
1991 Pontiac Bonneville LE
3800 V6 ( C ), Black/Slate Grey
~~~The Former Fleet ~~~
89 Cavalier Z 24 convertible
78 Holiday 88 coupe
68 LeSabre convertible
73 Impala sedan