Hyundai Motors of Korea has been selling automobiles in the U.S. for many years and has earned a reputation for producing a line of value-minded vehicles. As is often the case where inexpensive automobiles are concerned, many Hyundai vehicles feature rear drum brakes. This is particularly true for older Hyundai models. There are slight variations in the drum brake design used on the different Hyundai models and years, however, the basic service methods are similar. Hyundai owners can perform their own basic rear drum brake service by becoming familiar with the relatively straightforward maintenance procedures.
Park the vehicle on level ground. Put automatic transmission vehicles in "park," and put manual transmission vehicles in first or reverse gear. Loosen the lug nuts on both rear wheels about half a turn. jack up the rear of the car and set the car on safety stands. Remove the rear wheels.
Remove the drum retaining bolts or screws. On larger vehicles, there are usually two or four retaining bolts, while smaller vehicles may have one or two retaining screws, or nothing at all. Pull the drum straight off the hub. If the brake drum is difficult to remove, screw 8mm jacking bolts into the threaded holes provided on the drum face and tighten the bolts evenly to jack the drum off the hub. Some models have one hole, others have two, while others have no hole. If no threaded holes are present, firmly tap the outer surface of the drum with a rubber or plastic mallet to loosen it. Take care not to hit the inner rim of the drum.
Look for the adjuster wheel mechanism. This is a cylindrical assembly with a toothed wheel around its outside that is placed in between the brake shoes. Turn the adjuster wheel to relieve the spring tension on the brake shoes. You may have to lift the adjuster lever with a screwdriver in order to turn the adjuster wheel.
Remove the upper return spring by gripping one end of the spring with pliers and unhooking it from the bake shoe, then unhooking the other end. Take care not to damage the dust cover on the brake cylinder. Remove the lower return spring, the adjuster lever spring and, if present, the control lever spring and anti-rattle spring in the same way.
Remove the adjuster wheel by moving it up from between the two brake shoes. If there is a metal strut in between the two brake shoes, remove it in the same way.
Remove the hold-down pins that hold each shoe to the backing plate. There will be one pin for each shoe on smaller brakes and two pins for each shoe on larger brakes. Some models use retaining springs in conjunction with the hold down pins. For these, use a large screwdriver, hex wrench or pliers to depress and rotate each pin clockwise until the pin tabs line up with the grooves in the retaining washers that hold the spring in place, then pull the retaining washer and spring off the pin. Push the pins out through the back of the backing plate.
Some models use retaining clips with the hold down pins. For these models, use pliers to remove the clips and push the hold down pins out through the back of the backing plate.
Pull the front brake shoe off the backing plate and pull out the rear brake shoe assembly. Remove the parking brake cable from the rear shoe by removing the retaining clip with pliers and slipping the cable end out. Remove the retaining clip on the control lever pivot pin, if present, and pull the lever off the rear brake shoe.
Measure the thickness of the brake shoe linings and compare to the manufacturer's recommended minimum. This information can be found in the appropriate shop manual or aftermarket equivalent repair manual, or you can ask at an auto-parts store. If the lining thickness is less than the allowable minimum, or if the linings are damaged or show uneven wear, replace the shoes.
Verify that the drum is round and is not worn out. Check the inside diameter of the brake drum in several directions using a drum micrometer. The diameter should be the same in all directions. The interior surface of the drum should not have any deep grooves, pits or cracks. Compare the drum diameter to the manufacturer's recommended maximum diameter. This information can be found in the appropriate shop manual or aftermarket equivalent repair manual. If no manual is available, the maximum allowable drum diameter is normally stamped into the metal of the outside of the drum. If the measured diameter exceeds the allowable maximum, the drum is worn out and must be replaced.
Reverse the steps to assemble the brake. Use the opposite wheel as a reference. Reinstall the wheel. Pump the brakes several times to set the self-adjusting mechanism. Repeat the procedure on the opposite wheel.
When servicing rear drum brakes, remove the drums from both rear wheels so that the assembled brake can be used as a visual guide in reassembling the brake being serviced. It is also helpful to draw a large circle on a piece of paper or have something round like a paint can lid that you can place on the ground nearby and place the removed brake parts within the circle in roughly the position that they occupied in the brake. Step-by-step digital photos can also be a helpful reminder of how things should go back together again. When removing brake springs, vise-grip pliers work best. These pliers self-locks onto the spring end so you can concentrate on unhooking the spring instead of focusing on gripping the pliers.
Work in a well-ventilated area when working on brakes. Be careful when working on springs under tension. These can suddenly snap and possibly cause injury.