The SLS Valve controls the height at which the rear of the car sits. The lever arm position tells the valve to raise or lower the rear. The lever arm is moved by way of the sway bar. Which get rotated when the rear of the height of the rear end it changed. With the car running and unloaded the lever arm should be in the neutral position, which is parallel to the ground.

Before you get started be aware that moving the lever arm of the valve with the car running will raise and lower the rear end. If it's not lifted and securely supported by the wheels with ample working room you could squish yourself under the car. Now that I've scared you away, lets get to it.
It is a simple job, only a couple tools are required. You'll want two 10mm end wrenches, a 4mm diameter locking rod to lock the valve in it's neutral position, which is now available as part of my SLS Valve O-ring kits. This is best done with wheel ramps. The weight of the car needs to be sitting on the rear wheels as if it were on the ground.

1. With the engine off, remove the adjusting rod from the lever arm. You'll need two 10mm end wrenches. Don't just twist the nut off, you need to hold the other side or you'll break the ball joint.
2. Once the adjusting rod is off. Move the lever arm into the neutral position and insert the locking rod through the lever arm and and into the hole in the valve (As seen in the pic). You've now locked the the car into the proper neutral unloaded height.
3. Start the car and let the SLS system adjust itself to the height.
4. Then adjust the length of the adjustment rod if needed, then reattach. Remove the locking rod, and you're done.

There are a couple reasons your ride height when set to the proper height could still be too low or too high. If your springs are tired they aren't doing their job to the fullest and will allow the rear to sag a little lower than it should despite the valve being set at the proper height. Or if the valve has been rebuilt and the lever arm wasn't put back on in the proper orientation you could have the rear sitting too high or too low, depending on how the lever arm was put on. Stay tune for the proper alignment of the lever arm and rod.

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