I've got a 1988 GTA L98 700R4 with a little over 100,000 miles on it. Recently there has been an usaul sound in the transmission like a popping spring sound everytime I shift it into gear. My tranny still shifts perfect, and is otherwise like new. Does anybody know what this sound could be? I don't think all 700r4's do this or do they? Is this a sign my tranny may be on it's way out?