I've never found a service interval for PS/Suspension fluid. I changed my out after buying the car. Mine had a filter on the bottom of the reservoir cap and I changed that. The part number of the fluid was embossed on the cap as well. Probably discontinued but there would be a newer PN. The system recirculates. Some have disconnected the return line (top of cap) and flushed it out that way (engine running). Be careful as the filter provides back pressure. Without it, you may get an unwanted oil shower. I just changed the filter and sucked out the reservoir a couple of times and called it a day. If you aren't having any problem, there is no rush.

FYI - For late model MB cars, brake flush is every two years and coolant flush is every three years.

Enjoy the ride, the W140 has to be one of the best MB's ever made.

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Good luck.






1998 E320 Wagon