[lxfiveoh]

Underdrive pulleys are supposed to free up a few horsepower at the wheels by reducing the drag placed on your motor by the accessories.

Typically, they slow down there are a crank, alternator, and waterpump pulley. Hopefully, you have a high output alternator so you can avoid battery charging problems.

When I drove my 1990 5.0 daily, it wasn't a problem, but now that I let it sit and take it for only short drives about once a week, I can't let it sit too long, or it will be slow to start (or not want to turn over at all)....

I don't think my alternator is able to keep the battery charged on my short trips.

I don't think underdrive pulleys are supposed to make any noises. You might be thinking of a gear drive instead of a timing chain, but that's a whole other ballgame.

Good luck,