my M104 3.2-24v motor (93k miles running Castrol GTX 20W-50) is as quiet as my M119 (36K miles)= no rattling, no ticking, no clicking, no tapping, no squealing, no whining, no knocking, no pinging, no whumping, no thumping, no screaching, no whistling, no groaning, no moaning, no grinding, no tapping, no skipping, no rub-a-dub-dubb'ing....(this condition naturally -with the motor started/ running and/or moving forward/reverse at any speed to 130mph w/ full systems on including seat heaters)
I do have a minute little air pump noise when cold though- sounds like a worn bearing- but goes away in a few minutes and then silky smooth quiet- can't hear squat from the cabin (no stereo or climate control on and in a pillarless E320 Coupe)
you may wish to drop by a reputable exhaust shop to have the car lifted and inspected (gratis inspection)- thereby eliminating the exhaust heat shield possibility
fyi- there will always be a little more motor noise escaping when you open the oil filler cap- you just took the lid off and the inner working critters are busy managing the combusting in there)
good luck and let us know what turns out
Last edited by -fad; 09-28-2001 at 03:29 PM.