Hello, I have a Euro 84 500 SEL that I just purchased 1 month ago. After numerous repairs it is almost ready. This car has 4 hydraulic shocks which I am told is somewhat rare. There is a Suspension leveling valve in front (underhood) and one in the rear, under the car. The driver's rear shock and that rear valve are leaking. I just found a shock and valve from Potomac but before I install I was wondering if there is a certain procedure I should follow? I imagine this system would have to be bled somehow much like the brakes. There appears to be a bleeder screw in the line near this rear valve. Someone recently told me that weight would have to be placed in the trunk to start the fluid back to the shocks. To complicate matters, the few miles I have driven this car so far it seems that the ride is rough, almost bumpy. I read a thread on this site about these Nitrogen spheres (small 16-18" ball shaped reseviors for each shock) going bad which would cause the bumpy ride. I am now wondering how if any way there is to test those shperes and if all 5 should be replaced when I change out this shock and valve? Any advice would be greatly appreciated. Thanks, Bill