While the drain connection for a garbage disposal is nearly universal and fits standard sink drain holes of 3 1/2 to 4 inches, the size of the disposal unit itself is not. You must have enough space in the cabinet underneath your sink to accommodate the disposal's housing. A larger model may not fit in a compact cabinet or if the existing plumbing is arranged in an unusual way. Before buying a new garbage disposal, measure the available space under your sink. If you are replacing an old unit, it's often easiest to choose a new model of a similar size.

There are many maintenance and repair issues that lead to a malfunctioning garbage disposal. Regular clogs place wear and tear on the motors, leading to an eventual shutdown. Electrical issues at the breaker, wall outlet, or disposal itself can fry the unit. The most common cause is simply a worn-down motor. These motors can only handle so much use before powering down for good. 

Once you have your garbage disposal disconnected, you can remove the mounting bracket by unscrewing the bolts that are holding the bracket. You can back them out just enough to pop off the snap ring, which prevents the bottom portion of the bracket from disconnecting from the top when you unscrew the bolts. Use a regular screwdriver to pop off the snap ring, and the rest of the components should fall off by themselves.

As with many appliances, proper maintenance is key to maximizing your garbage disposal’s life span. If everyone in your household is on board with proper care and maintenance, like running water while operating the disposal, you should get plenty of years out of your unit. Avoid putting the wrong food items down the disposal, including pasta, rice, bread, and more.