This mysterious clunking.... Every time I shift gears, doesn't matter which gear or how fast I'm going I hear a sick clunk from my rear end area. I just replaced my tranny fluid, and I had no metal flecks or anything to tell me something was wrong with it. I replaced my rear pinion seal, and although I had lost alot of fluid there didn't seem to be anything wrong with it. I go to school for auto tech, I can't figure it out, and neither can my instructors. Wtf is going on? must be rear differential right??? It's a 97 GT. Please help me it's driving me nuts. Another symptom is me having to wrestle to get into gear sometimes, and i see no clutch or tranny problems. This might just be the way mustangs are though.