i have a 1992 gmc suburban c 1500. i lost rear brake fluid do to a rused line. replaced line now when i bleed rear brakes with key on i get now fluid out of bleed screw.

National organization of women? Man, that thing must be angry. He/she may just need to apply the brake, helper opens bleeder. shuts bleeder. lift pedal. apply pedal, open bleeder, close bleeder. lift pedal. repeat repeat til fluid present at bleeder. If too much leaked out, may have to bleed the master cylinder. If line was empty, raise rear of vehicle and stroke the pedal, takes an educated stroke to finesse it. eventually, it will cooperate. Or raise the rear very high, use blocks flat on the floor under the jackstands. Had to do this before with minimal supplies and that helped. Try jacking the back of the truck higher

Pumping would tend to aerate the fluid, be gentle, and tenacious. long strokes, not all the way to the floor. stop 3/4 of the way and let the helper shut the bleeder

Vehicles with ABS may need to be fully raised and operated to cycle the valves in the ABS unit. If you were able to drive it, carefully? safely ? Or make it think so ? You may not need a bleed tool for ABS

If this has an ABS pump, you are best advised to use a battery charger during the procedure to keep from losing power to start.