Volvo Repair: Squealing sounds, rubber seals, waterpump

Question
We (my son's girl friend at college actually) have a 1988 740 that has a squeeling sound that we think is steering related, but can't pin down. It seems to come and go. I am told it is loudest when you start to drive, but may be there sitting still with the engine running. What is the most common part to fail here to give this sound? Recently the sound is stopping with a "thrick" sound. Fluid levels seem OK. Belts look good. Replaced waterpump to get new set of rubber seals for it since the top one was leaking.  

Answer
it could be the crankshaft dampener pulley on the front of the engie.this is a 2 piece metal pulley with a rubber ring between the 2 halves. this rubber gets old and the outer pulley slips on the rubber this is easiest to tell by using a timing light where you can see the timing mark moving around which it should stay in one place.

Rege