A: Disable the air suspension system if vehicle had it. Loosen lug nuts, then lift back of vehicle and secure on jackstands. The front wheels must be blocked to keep the vehicle from rolling off the stands. Take away the rear wheels, then remove brake drum. If the drum sticks because of corrosion between axle flange and wheel studs or brake drum, apply penetrating oil around flange and studs and let it soak in. Strike around studs with hammer and flange to free drum, then strike around back edge of drum to remove it. If excessive drum wear locks drum onto shoes, knock out plug in access hole in backing plate; insert screwdriver through hole, push actuator lever off star adjuster and back off adjuster wheel with another screwdriver or brake adjuster tool to retract shoes. Clean brake assembly with brake system cleaner before starting work. Remove secondary brake shoe retracting spring; then remove primary shoe retracing spring. Disconnect brake shoe adjusting lever cable from brake shoe adjusting lever; remove them both along with spring, upper end of cable from anchor pin, anchor pin guide plate from anchor pin, cable guide, parking brake link and spring. Use hold-down spring tool to take off front hold-down spring assembly which includes upper washer-spring-lower washer-pin; disengage brake shoe adjusting screw spring from shoes; remove rear hold-down spring assembly; pry E-clip retainer off with small screwdriver; disengage parking brake lever pin from rear shoe and take out parking brake lever. Lubricate backing plate's shoe contact points with high-temperature brake grease.Put washer on parking brake lever pin ,insert pin through new rear shoe & put E- clip retainer by squeezing its end together.Install hold-down pin through holes in backing plate& rear shoe putting rear hold-down spring assembly so that by giving it a 90-degree twist with a hold-down tool would lock into place.Put guide plate on anchor pin,install brake shoe adjusting lever cable on anchor pin; mount brake shoe adjusting lever cable guide on rear shoe. Hook short-end of secondary (long) shoe retracting spring into hole in cable guide and into rear shoe and long end over anchor pin.Thread brake shoe adjusting lever cable over guide.Place parking brake link & spring ensuring that link is correctly engaged with parking brake lever & secondary shoe.Put primary(front) brake shoe assembly in position ensuring that it is properly engaged with parking brake lever link.Insert hold-down pin through holes in backing plate and front brake shoe then install hold-down spring assembly giving the hold-down spring assembly a 90-degree twist with hold-down tool to lock it into place.Hook short-end of primary(shorter)brake shoe retracing spring into this hole in front shoe and hook other end over anchor pin.Install Brake Shoe Adjusting Lever Spring such that straight end points towards rear brake shoe but hooked end faces forward.Install Brake Shoe Adjuster Lever.Hook end of adjusting lever spring over adjusting lever .Hook lower end of brake shoe adjusting lever cable over adjusting lever .Hook short-end of lower shoe retracting spring into front shoe; hook long-end of the same spring into rear one. Engage rear part adjuster assembly with its notch in rear shoe ; pull front one slightly forward and engage its front end adjuster assembly with notch in front one.Clean check drum for score marks, deep grooves, hard spots(which will appear as small discolored areas), cracks; if worn, scored or out-of-round it can be resurfaced by automotive machine shop.Repeat this procedure for the other rear brake assemblys.Install drums. Pump brakes several times ,then turn adjuster star wheels using screwdriver inserted through hole in backing plate until shoes slightly drag on drums as they are turned.Back off adjuster now until shoes don't drag on drums.Install rear wheels,install lug nuts ,lower vehicle and tighten wheel lug nuts. Check brake pedal position. If brake pedal goes too close to floor, further adjustment of brakes is required. Back vehicle up making repeated stops to actuate self adjusters which work only when vehicle is in reverse.Test brakes for proper operation before driving in traffic.