1981 Chevy Truck loud noise

I was driving my truck home the other day and it started making a sqeeling and grinding sound. When I was about to turn in to my neighborhood the engine died. I tried to start it, but it was really hard for it to turn over. Every time the engine turned over it made the loud grinding and sqeeling sound, but would eventually start and continue making racket. We tested the battery, it was 12.4 and when we started the truck it went up to 14 volts, so the alternator fine. The power steering pump is full of fluid and the wheel turns fine. All the noise seems to be coming from underneath. A friend of mine is an ok mechanic, and he thinks that it may have a bearing in the crankshaft had slip, but with it running for about 15 minutes off and on making that racket he thinks the damage may have been done to the crankshaft and just putting a new bearing in would just be a band aid to the problem. What do you think? Ask me anything and I will try to answer to the best of my ability.