I have a 2004 f150 4X4 40,000 miles with a rear parking brake problem.
After paying too much to solve it once, I thought I'd give it a try myself and am looking for advice.
I believe my rear brake(s) tend to lock up.
Based on internet comments, I believe it's a rust problem located in the brake cable or in the "scissor pawl" or in the "equalizer". I've not dismantled it yet, and thought I'd ask if anyone knows what/where is a scissor pawl or equalizer?
Does anyone know of a source for a diagram including either or both of these devices?
I just got done rebuilding my parking brakes due to a rear axle seal leak. The "paw" that everyone refers to is just 2 pieces of metal located on the top of the brake backing plate that pivots on a pin in one of the pieces. The two pieces rust together which causes the shoes to not move towards the rotors with the movement of the parking brake cable. I would get the rear of the truck in the air..... securely position the rear on jack stands and block the front wheels. Then remove the tires. Then remove the calipers and rotors. you my have to use a block of wood and a hammer on the rear of the rotor surface to get it off the axle hub. Next you wil see the shoes and springs. Remove the top and bottom springs using a pair of pliers. Then depress the clips in the center of the shoes and slide them off the retainer pins. Now the shoes and pins will fall out. The parking brake cable hook can now be removed from the "paw". The "paw" or acutator should be 2 pieces that can be taken apart. If they are rusted together some penetrating oil and a few taps of the hammer can separate them. I would try to recondition them by using a file on the mating surfaces to remove the rust. Next put a big glob of water proof grease (wheel bearing grease) between the acutators and reassemble. Also make sure the parking brake cables are moving freely before reassembly. Next reinstall the shoes, rotor and caliper. Put about 3 lugs on to hold the rotor in place. Next remove the rubber plug in the rear of the backing plate. You will see the adjuster teeth through the access hole. Next start the truck and put in drive. Crawl under the truck and adjust the shoes untill you hear them rub on the inside of the rotors. Then back them off a 1/8 to 1/4 turn untill they are quiet. Reinstall the tires and go for a test drive.
Thanx "black04fx4" for the clear reply with explanation.
One of the service manuals recommends an additional step...pull the brake cable and use a 5/16" drill bit to lock it in place. I'm unsure what they are getting at....or why they are making their recommendation...does it make sense to you?
I believe that step is to prevent the cable from pulling back through the brake backing plate. There was no tention on my cable and it stayed put. I would be easy enough to fish it back if it did pull through.