Paul,
You may actually be impressed with a pressure RISE with the right synthetic. My oil pressure has ALWAYS gone down to as low as 0.5 bar in drive, at idle, in hot weather (and I got the car at 25,000 miles and it did it back then). As you know from your owner's manual, anything above 0.3 bar at idle (at least for my car) is considered OK by MB.

Since I switched to Mobil 1 15W-50, it never drops below 1 bar. Even when I use 5W-30 Mobil 1 in the winter, the pressure stays above 1 bar (but of course the ambient temp is lower then too).

Try it, you'll like it!

__________________
Steve
'93 400E