Rust, missing, weak, or broken springs, wheel cylinder sticking, or parts assembled incorrectly. On a 46 year old car I would replace all wheel cylinders and the master cylinder unless they have been replaced in the last few years. Replace all brake fluid and bleed the system. Clean all rust from every part. Install new springs and make sure everything is assembled correctly.
My 1971 Ford Mustang , fastback , with 351 Cleveland , 4 barrel , had drum brakes on the front
that depends greatly on what is wrong with them.
does you truck have drum brakes in the back
Driving through a cow pasture.
Its a bad cylinder spring
On the bottom of the back side of the drum, there is an oval, black rubber piece. Remove it and there is a gear inside that is used for adjusting.
worn out pad, warped rotor, broken brake caliper (or cracked drum, if drum brakes)
My sources show there are different part numbers for spindles on the 1967-70 (drum brakes), 1971-72 (disc brakes) and 1973-87 (disc brakes).
Yes. Disc and Drum brakes mount differently, each uses a different spindle. Brake lines, hoses and master cylinders are also different.
( 1 ) on each of the rear drum brakes
What about 1993 Pontiac drum brakes, please be specific.
Drum brakes.