Based on your observations, I'd suspect a brake pad wear indicator is squeaking. They commonly stop making noise during braking because the pads straighten out and the "squeaker" moves away from the rotor. Time for a brake inspection.
March, 8, 2012 AT 1:23 AM
It also could be a dry ball joint. Been there.
March, 8, 2012 AT 7:02 AM
We love Blazers because they eat ball joints. We get to replace them every two years, but they don't stop squeaking during braking. While they do squeak at first, clunking is more common with them.