These kind of problems can eat you alive..It could be anything from the calipers to ball joints,tie rod ends and even upper strut rod bushing (bearing). One of your calipers can be hanging up a little either by the pistons in the caliper not realeasing all the way causing drag and heat ,to the slider for the caliper to float on causing one side to run way hotter causing uneven braking in the front end.I'm sitting here shaking my head like I have parkinsons cause I've been thru a mess of these situations...after you had it aligned the veh should ride true,new model alignment machines (lazer style)are very accurate...however they test the car sitting still,with no suspention movement,I've seen situations to where a blown front strut caused the problem,to where when you hit the brakes the bad strut causes the car to dip unevenly in the front causing uneven weight distrubishion in the front causing a pulling effect,next tie rod ends inner or outter,rack and pinion you can't see the inner ones,to check for that you really need to put it on the rack grabbing the tires from side to side as if your trying to turn the car by the tire and feel for play,if so have some one do that for you while your looking to find out where the play is,look for oil leaking from either strut,for possible blown strut.after car is back down on the ground go from corner to corner of the car trying to bounce car and check for car recoil.another possiblity...hope that helps you...good luck in your adventures....Rusty Parts