Thanks for the replys....going to try and flush the entire thing this afternoon after work. I'm really thinking that it's clogged up because last night I opened the petcock on the radiator and there was barely a dribble of coolant coming out.

If it is clogged, what is the best method of flushing the system? I was thinking of putting a tee in the heater hose a doing it from there.

The temp gauge reads about middle of the "normal" range when it's warmed up.

Where is the heater control valve located and is this something I can test at home?

Oh, and I forgot, it's a 3.0 V6, 2wd, A/T.