i dont know, but brake fluid has to get pretty hot to boil, and when it does boil it causes air and air dont lock up brakes that i know of. brake pads get hotter sometimes than headers, it wouldnt hurt to insulate it like NTFDAY said and see . it sure won't hurt anything. if you dont have any, put something between the header and line and tyr it. let us know what it is. i dont think thats it, but now you got that on your mind you need to do something about that first. are all the wheels locked up?