Every once in awhile my shifter will not shift out of Park. I am about to take a long trip so I don't want to get stranded somewhere because it won't go into gear.

Can someone confirm for me whether or not the brake pedal must be depressed to shift out of Park? It is a K1500 '95 Suburban. I am wondering if there is a solenoid somewhere that keeps it in Park until the brake is depressed. Maybe that solenoid is sticking and not releasing the linkage? Or maybe the linkage is loose if there is no solenoid present?