The tail end of my Benz was dragging because the hydraulic leveling system was not working. No one seems to know repair or maint. inf. So, I open the bleed screw near the back and out shot air and foamy fluid. I drained it down completely, the resevoir was full, but the shocks did not pump up. Does anyone know the procedure to bleed and refill. Where can I find the tech data for the maintaince and repair of the system. Thanks to anyone who can help.