Further to Rod's comments about not using white spirit.
Last Spring I decided I would give my alko stabiliser pads a clean before starting out although I had no reason to think they were dirty. I used white spirit and the stabiliser made the most horrible racket until I reached my destination. When I checked the towball there appeared to be a coating of some description on it. A light rub with wire wool then a wipe over with kitchen roll and everything was fine again.
Since then I have bought a can of brake cleaner from Halfords and no further problems. I would agree that white spirit should not be used.
Robert