I accessed mine from the topside by removing the oil cooler lines was it worth all the effort? Yes, now I get the right readings, previously the pressure ran between high and higher, never dropping down when the oil was hot.

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'95 E320 Wagon my favorite road car. '99 E300D wolf in sheeps body, '87 300D Sportline suspension, '79 300TD w/ 617.952 engine at 367,750 and counting!