95 E320 oil pressure

[tbenner]

Say it isn't so... I have been running Mobil 1 0w40 in the 95 E320 wagon for a year and a half with no problems. Now when warm, it is dropping below 1 bar oil pressure at idle when it is in gear (slightly less than 500 rpm on the tach). In park at idle (slightly above 500 rpm) it hovers around 1 bar. It used to stay around 2 bar at idle. The pressure does peg at 3 bar when driving.

I am at a loss as to what to check or do. There isn't any oil in the coolant or vice versa. Do the senders and/or gauges go bad? Do the oil pumps ever go bad? Would the bearing clearances open up seemingly overnight so it won't hold pressure at low rpm? Should I just change it to heavy dino oil and see what happens? I like this old wagon and would really like to keep it on the road.

Thanks for the help and advice.

Tim Benner
Dayton, Ohio