Is this normal?
 

While sitting at a lite today,i noticed that the oil pressure guage dropped down to O on the guage, so i put it into neutral and it went up almost to the 1 on the guage.I checked the oil and it was on the full mark.Is this a bad sign of things to come?

Not normal.

Sixto
95 S420
87 300SDL

Sixto: What do you think the problem is?

What weight oil are you using? Is this a sudden change?

Castrol-15-40 and this is the first time this happend.

Well, could be the sending unit, the gauge, the oil pump, engine wear...

You might try 20/50 and see if the pressure comes up any.

Sounds electrical, could you put a mechanical guage on these cars to get a more acurite reading? I never trust electric guages.