A simple test that worked for me to finally prove it was the bags,
raise the suspension to offroad height on the driveway.
Cover the bag in soapy water and measure the height from wheelarch to wheelhub. disable the sls by leaving a door open
Jack up once side as high as you can get using the bottle jack.
Release the pressure in the jack very quickly and allow that side to drop at speed. Make sure you have nothing precious near the wheel!)
Check airbag for froth and re-measure the height.
Repeat entire procedure on other side. Always worked for me when leak checking
