hey dude you might have a rock jammed between the clutch bell and brake disk. That happened to me. I was driving around and my truck shut off. I thought it was out of gas and checked it had a half tank. Started it back up and gave it full throttle and it didn't move no more than 2mph. Here there was a rock jammed got the rock out and it still didn't move. Checked it again and found out that my brake disk was bent. so check that stuff out.