I'd suggest you check in the owner's manual. There's two different sway controls available, don't know which you have. It definitely reduces power and applies truck brakes on wheel that will reduce sway. It doesn't cancel out bad loading of trailer or replace an anti-sway hitch. Going down the road with trailer swaying and brakes alternately applying and releasing sounds like a great boon to brake shops and gas stations.
Bob & Donna
'98 Gulf Stream Sun Voyager DP being pushed by a '00 Beetle TDI