My 88 k5 has had a driveline clunk noise for some time now. I can't seem to figure it out. It happens when I accelerate from a stop position. I can feel it through the floor underneath my feat. I thought it was the wheel bearings coming loos or something easy like that, but it's not. Iwas also thinking it could be the t-case bearings, haven't check yet. Any thoughts or suggestions are appreciated. Thanks.