Just got my 5.3l swapped 79 chevy out on the road to drive around a little and i noticed that when i am decellerating there is a loud rubbing noise coming from what seems like the transmission. It almost sounds like the driveshaft is rubbing on something but i have checked and it isnt. I looked under the truck and there is a small dent in the transmission pan near the rear drivers side. Is there something in that area that would cause this. I noticed it before but i assumed that was just were the fluid was so no biggie.