My parking brake cable broke and i need to repair from pedal to rear axle on 87 gmc sierra 4 by 4 350 5.7 litre. need to find price and product number

I should have disengaged when it broke if not it is jammed some where and not releasing so raise the rear and follow the brake cable to the rear axle and remove cable try rotating wheels if no joy remove wheels and tap brake drums and try rotating drums if still no joy try stripping brake system down on rear axles to free up internals

Test voltage on wires when use brake pedal, if you have voltage, could be some harnesses go to bad, or, somr broke wires.

Could be several different things that may be causing the parking brake. The sierra uses a simple cable pull system. If the cable becomes loose you will not have emergency/parking brakes. If the cable is tight then the shoe located inside the rear brake drums is worn or broken. If there is no cable coming from the parking/emergency brake pedal inside the cab then it has been either broken out or removed at some point, which is easy to do if taken off-roading.
Keep in mind that only the rear wheels have parking/emergency brakes. Front wheels have none.

make sure you clean and oil e-brake arm, the spring might have broke, or little lock arm could be sticking . put wd40 all over asembly, any moving parts, you might have to move lingage on side back and fourth to loosen up start there. good luck.

The cable splits under the cab. One side to the right rear-one side to the left. There is an adjustment under there as well to take up any slack.
Have you repalces your rear brake shoes? As they wear out, your parking brake cable wll become slack. You need to see how much pad you have left.

The adjuster is just like on a car with drum brakes. It can be adjusted with the wheels still on the truck, but if yours is out enough that it doesn't work, an inspection is warranted. Axle seal failure is common and will soak the shoes.

Jacked both rear wheels off ground, and while slowly spinning wheel, tighten the star-wheel adjuster until you just hear and feel brake drums rubbing, then loosened slightly.
There's a plastic dust cover about 1/4" X 1" that you remove, and use a drum brake adjuster tool.

The driverside access hole is below axle, easily accessable. To tighten driver side rear parking brake, turn star-wheel adjuster down.


The passengerside access hole is found above axle, and difficult to see. Removed pass side wheel and used an inspection mirror.
To tighten passenger side rear parking brake, turn star-wheel adjuster up.

Good luck and hope this helps. Oh and the other thing to is that if you do smell axle fluid around the wheels and see oil leaking from the drum area. Then you have a axle wheel seal and or bearing gone bad too.

Providing that the rear portion is free and not damaged you only need the part that broke. Your dealer can give you part # and advise if warranty covers it.

Look up under dash where brake pedal pivots, you should see a switch that is activated by pedal arm.

Can you get to any part of the cable? If so, use a pair of pliers to release it until you can replace the cable.

Sounds like a rear end ratio problem ECM malfunction