ORIGINAL: mbx5prospec

I always use WD40 to clean my car, I spray it on the blow it off, but taking my car a part I noticed that all hinge pin assemblies have a black gook type of residue that seems to actually create a resistance in the arms movement. I'm starting to think that WD40 isn't really the thing to clean your car with? What do you guys think? I think I'm just going to air clean my car... One of the guys at my track do this, all he uses is the air compressor and a tooth brush