Just dug this thread up because my 91 300E with just under 150K is doing the same thing. Ticks for about 5 to 10 seconds at startup, with no oil gauge reading, then eventually ticking goes away and gauge is pegged at 3. If the car sits a couple hours, it's OK, but any extended sitting and the ticking will occur again (like overnight).

Are you guys sure this is normal?

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