Drawer slides are two-piece metal slides that mount between the drawer and the cabinet or frame. The drawer uses these slides to open and close easily, and the track keeps the drawer level. Over time, the screws used to attach slides to both the cabinet and drawer may pull away. This will allow a drawer to be pulled and twisted as the next person tries to open the drawer when the slide is no longer lining up. This will often bend the slide. It is easier and less time-consuming to simply replace bent slides rather than try to straighten them.
Remove the contents from the drawer. Pull the drawer toward you while applying lifting pressure. Most slides have a slot where the drawer portion drops into the cabinet portion. When you reach this slot, the drawer slide should separate from the cabinet slide. Some slides have a latch to prevent accidental removal of the drawer. If the drawer won't lift, look for the latch and open the latch so that the drawer can lift out.
Remove the slides from the inside of the cabinet and from the outside of the drawer. Take a moment to examine the drawer to make sure it is sound. Sometimes when a drawer is pulled at an angle several times, screws or nails may loosen. Tighten and reglue the drawer if it is loose. Note the location of any damage to the mounting location of the slides.
Bring the slide to the store to be certain you purchase the exact type and length you need. You will want to replace both slides as each type of slide is slightly different, and an old slide may open or close differently than a new one.
Position the outside left portion of the slide even with the bottom of the drawer opening. The front of the slide should be flush with the front of the cabinet. Screw the slide to the cabinet. Check for level before screwing the back screw. You can screw into any of the nail holes from the centre of the slide to the back. This will allow you to avoid any previously damaged wood for a secure fit. Repeat with the right side.
Place the left-side drawer slide against the bottom left side of the drawer. (The wheel portion is to the back.) There is a lip along the edge of the slide that should fit against the bottom edge of the drawer. The front of the slide should touch the back inside of the drawer front. Repeat for the right side.
Hold the drawer at a slight angle with the back side lower. Slide the drawer into the cabinet until the wheel drops through the slot into the cabinet slide. Lower the drawer to level and it should open and close easily.
Empty and remove the drawer from the cabinet. Turn the drawer over and examine the track. Look for missing screws, nails or splits in the wood. Look for bows in the track or missing wood.
Straighten the track. You may need to remove and replace missing screws, nails or staples once you realign the track. Often the track can be repaired simply by replacing missing screws, nails and staples. Most drawers have tracks in the centre that mount to a track in the centre bottom of the cabinet. Check both the drawer and the cabinet sections for damage or problems.
Purchase a drawer track guide that mounts to the back of the drawer. This guide helps the drawer stay on the track.
Some cabinets may need blocking along the inside for mounting screws. Simply cut blocking wood to fit and attach the wood to the cabinet at the locations you need. Blocking is just a filler wood to give you a good surface to screw into.