This is usually just a result of OEM gauges losing accuracy over the years. Oil-pumps rarely fail. If you've started to notice a clattering or ticking sound coming from the top of your motor then you know you're having an oil starvation problem.

Just to be on the safe side i would have the Oil Pressure checked by a new gauge either from a garage (this is a common procedure) or just replace the oil sending unit with an aftermarket piece from your local parts store.


Also, make sure that your oil dipstick is firmly seated in the tube, and check for loose hoses around the valve cover. Have you changed your oil filter lately? Switched brands of oil filter or different weights of Oil? If the engine doesn't have proper Positive Crank Ventilation PCV then you will see a drop in oil pressure. Also depending on vehicle mileage the clearances between those bearings are growing and sometimes a thicker weight of oil can help cushion the aging bearing clearance issues.

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93 300 D 2.5 turbo