So the the SLS is NOT supposed to make noise when raising and lowering?

mine makes the same noise near the valve when lowering.

If you remove weight from the rear, the springs rebound, the rear raises, and the control valve compensates by releasing fluid.---This was my supposition to the recurring sound. If you bled your system using the bleeder on the valve in the rear, there shouldn't be air in the system (unless there are leaks). Air should also be forced out of the system naturally.

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