For quite a while now I've experienced a clunk when I go from P to R or D. I've seen the videos telling me to grease my driveshaft, but it still occurs. If I'm on a slight incline ( front end merely an inch above the rear) it won't clunk and shifts smooth; vice versa. If I'm on flat ground it'll clunk in both directions. Additionally, (I especially notice it at yielding signs) if i let off the brakes too fast and get on the gas it'll also clunk. I guess aside from grease what's normally next to inspect for wear? Thank you guys.