RedneckTA

I'm thinking this is tranny related, which is defnitely not my area of expertise, but here's what's up. ANYTIME I pull off in first (not dumping the clutch or gettin on it in anyway) I get a noise that kinda sounds like rattling/clanging. It definitely sounds like metal on metal rubbing. I thought maybe is was coming from the rear (a buddy had the same problem and changed his fluid and it went away) so I changed the fluid, but it's still there. The reason I think it may be tranny related is because when I ride the clutch when I pull out in first, it doesn't make the sound. Also, it sounds like it's coming from right under my shifter. The sound only comes in when I pull off in first and reverse, so it's only from a dead stop when I begin to roll. Any chance it could be the driveshaft, maybe a loose u-joint?