After a 3000 mile drive to California I noticed the hydraulic fluid level had dropped to almost nothing. I put the car in the air and checked for evidence of a leak--but could not find anything obvious at piping unions, the vacuum pump,or rear dampers. Where should I be looking?.I did do about 100 miles on a very hilly road that caused the car to attain full suspension compression at speeds approaching 80 mph. Any ideas?.

A clarification on my posting regarding fluid loss. I am talking about the leveling suspension system. When I loaded the trunk with luggage and a tool box for my vacation I drove the car and heard what sounded like a fan blade lightly contacting a fan shroud. The sound varied with engine speed and then went away after about 5 minutes of driving time. I am now thinking this was the vacuum pump kicking into action to pump fluid to the rear suspension. I am assuming there is a sensor/switch that determines the "rake" angle of the car when loaded--and activates the self-leveling feature on this model. Is that correct?.

This setup uses a hydraulic pump that is connected to the front of the engine. I you heard it there is a problem. I have never heard one operate. You may want to check your oil and see if it went in there. The seal can blow out and go into the engine's oil supply.

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Benzmac:
ASE CERTIFIED MASTER AUTO TECHNICIAN
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