Drum Brakes - Rear Brake Drum Adjustment

Cable System
If only one wheel is receiving braking, inspect the complete braking cable system for signs of a damaged or binding cable or a malfunctioning "equalizer" (check your manual for specifics). If all is working smoothly, the shoe replacement procedure/adjustments should correct this, as the brake shoe adjustment on the suspect wheel is likely the culprit.

Pedal Height
Check brake pedal height by pushing down on the pedal. If the brake pedal seems a bit "low" (although firm), try applying the parking brake then rechecking the height. If it is now higher, over-tightening of the parking brake is suspected, which will be corrected by our outlined adjustment procedure.

Return Springs
All return springs involving parking brake or brake shoes should be inspected for damage, and replaced as needed. After you have done this brake servicing procedure and just before you put the drums on and bleed the hydraulic system, you first want to determine if the parking brake adjustment is set correctly. Depending on design, the brake shoes, when viewed from the top, should be making firm contact with either the anchor pin, or the wheel cylinder contacts (absence of an anchor pin would indicate this design). If not, you'll have to loosen the parking brake adjuster until contact is made for both left and right wheels. Poor return springs, or a binding/malfunctioning cable/equalizer could prevent success here.

More Adjustments
Now, with that done, we can adjust the brake shoe adjusters (yes, that sounds a bit redundant, but stay with us here). It should be said that certain imported vehicles have excellent self-adjusting mechanisms, which move the brake shoes into perfect adjustment with nothing more than a couple of firm applications of the brake pedal. We will discuss the other widely used system involving the star-type adjuster. These should always be cleaned and lubricated as part of the brake shoe replacement procedure. Since there is a left- and right-side adjuster, make sure that they are installed on their respective sides. Some actually have an L or R stamped on them, but if not, look at the relationship between the ratchet teeth (star) and the adjuster pawl (moved by the adjuster cable). Most pawls move upward, during self-adjusting operation (important to verify this), so the "flat" portion of the ratchet teeth should aim down. Got it? If not, please get professional help to properly finish the job.


Now, you're ready to adjust. By all means, use the slot in the backing plate or in the drum itself to insert your adjusting tool through, so you can make the adjustment with the drum on. If no slot, you'll have to keep removing and installing the drum during the adjustment procedure, until you get it right. Keep increasing adjustment until there is a slight drag on the drum. Tugging on the parking brake cable during this procedure will "center" the shoes, so you can get a more accurate adjustment.