1997 Suburban 4x4 had booster and master brake cylinder replaced about a year ago.
Now in rare circumstances the brakes seem to stick on.
If you do a long slow breaking such as for a long freeway exit the brakes will stick on and remain on after you let off the brake (the pedal stays depressed).
Revving the engine seems to be the solution and the brakes release and the pedal comes back up.
On very rare occasions something makes a very loud wheezing noise which sounds like it is from inside the car.
Other than this "oddity" the brakes work fine. In fact, it is hard to get the car to engage in the behavior but it does happen somewhat regularly (never with a tech in the car).
Driving 10 miles up and down a mountain pass does not cause the problem.
Just the occasional long flat freeway exit.
Any ideas?

 

Got to be a Booster problem.