Pre-76 CJ-5 has four-wheel drums (11"x2" front and rear); 1976-83 has 11" disc front and 10"x2" drum rear. Adjust by turning the star wheel out until light drag is felt, then back off two to four clicks. Re-adjust every 6,000 miles or when pedal travel grows.
The CJ-5 ran two completely different brake configurations across its production. Before 1976 it was four-wheel drums — 11x2" front and 11x2" rear on most years. Starting in 1976, AMC switched to a front disc/rear drum setup, with 11" rotors up front and 10x2" drums in the rear. The rear drums are not self-adjusting on most years. They drift out of adjustment as the shoes wear, and the pedal goes lower and lower until somebody runs a stop sign or backs into something.
Manual adjustment is the answer. Behind each drum is a star-wheel adjuster — a small toothed wheel on the bottom of the brake backing plate. Turn it one direction to spread the shoes outward (tighter brake), the other to retract them. The adjustment hole is on the backing plate itself or on the back of the drum, depending on year — a small rubber plug covers it. Pop the plug, slide a brake spoon or flat screwdriver in, and click the wheel.
The right amount of adjustment: tight enough that the wheel takes solid effort to spin by hand, but not so tight that it locks. The standard procedure is to tighten until the wheel barely won't turn freely, then back off two to four clicks until the wheel spins with no audible drag. Both sides need the same number of clicks — otherwise the rig will pull under hard braking.
Drum brakes are honest when they're maintained and dangerous when they aren't. The leading shoe does most of the work in forward stopping; the trailing shoe handles reverse. Pedal that feels low after a few miles of driving — but pumps up — is usually wheel-cylinder fluid leaking past the cup, not adjustment. Pull the drum and look for any wet streak or fluid pooling at the cylinder. Wet means replace. Dust means clean and adjust.
The pre-76 front drums are the weakest single point on a stock CJ-5 brake system. Many owners convert to the front disc setup using a salvage 76-83 Dana 30 spindle/hub or an aftermarket conversion kit. That's a different job — for now, if you're staying drums, the discipline is regular adjustment.
| Part | Vendor | Est. price |
|---|---|---|
| Drum brake hardware kit (front, 11x2) | Crown / Raybestos | ~$22 |
| Drum brake hardware kit (rear, 10x2 — 76-83) | Crown / Raybestos | ~$18 |
| Wheel cylinder (rear, 10" brake) | Crown | ~$22 |
Written and maintained by an AZ wheeler and driveway wrencher. Always cross-reference your factory service manual — modifications affect vehicle safety and warranty. Work at your own risk.