98 Blazer noise question

When I shift from park to drive and vice versa I sometime's here a clunking sound.What are possible problems? Also engine sounds loud at high speeds and quiets right down when decelerating.Thanks!

MT2500 has answered in your original thread, here is where it's located: http://www.automotiveforums.com/vbulletin/showthread.php?t=751848