We recomend every 60k for fluid and filter changes using the Benz fluid. The .6 has a paper/felt type filter that is effective at catching the garbage but, will restrict a bit over time. (just like any decent filter) If you drop the pan dont flip out about carbon type debris in it, thats normal.
Project Smoker, '87 603 powered wagon
Hauler, 96 CTD can you say torque?
Toy 73 Cougar xr7 convertible
Acme Automotive Inc.