Knowing when it's time to replace your garbage disposal can keep you from throwing away good money. Sometimes the writing is on the wall and there's simply no doubt. But if you're unsure of what to look for, it's easy to fall into the repair trap. Even the best garbage disposal won't last forever. The International Association of Certified Home Inspectors (InterNACHI) estimate that a home garbage disposal should have a life expectancy of up to 12 years. Whether your disposal lasts that long will largely depend on how you treat it.When to Replace Your Garbage Disposal Quick NavigationFrequent ResetsLeakingPersistent OdorExtended Grind TimeUnusual NoisesFrequent ClogsNo PowerPlanned RenovationWhen a garbage disposal begins to struggle performing it's job, there are a few things it'll start doing (or not doing). Each of these signs are related to a different problem, however, in most cases they're a good indication that it's time to purchase a new garbage disposal.Frequent ResetsWhen too much strain is placed on the motor, the motor becomes overloaded and causes the disposal's internal circuit breaker to trip. When the reset button (on the bottom of the disposal) is pressed, electricity is restored to the unit, and the garbage disposal should operate again. When the waste load is too large, or a clog forms, the motor will typically shut down. This automatic shut down is simply a built-in safety precaution to protect the motor from burning out.If your garbage disposal needs to be reset every so often, there's probably no need to worry. But if you start noticing that a reset is necessary on a frequent basis (a few times a week or more) there's a good chance you have a more serious problem.It could be that the wiring has either become loose or it wasn't wired correctly in the first place. If this is the case, you'll need to hire a plumber or electrician to safely fix your disposal. Another more common cause, is your garbage disposal is simply aging out. As motors age they become weaker and begin to fail, causing them to overload far easier than they did in the past. If the problem is the motor, your best bet is to replace the garbage disposal. It isn't cost effective to replace the motor. Plus, disposals have probably advanced significantly since yours was installed. Today there are disposals on the market that are so quiet you hardly know they're running! LeakingThere are many reasons a garbage disposal can leak. Some leaks are serious and some are fixable.Connection LeaksIt's not uncommon to see a leak develop around the sink flange. If this is the case, you may be able to solve the problem by tightening the rings or redoing the plumber's putty. But in some cases, especially if the leak wasn't noticed in a timely fashion, a new garbage disposal is your best choice.Another frequent leak is in the dishwasher connection. If this is the case, you may be able to tighten the clamp or replace the hose to stop the leak. If water is leaking at the drainpipe connection, try tightening the bolts. If that doesn't help, you may need to replace the gasket.Internal CracksA more serious problem is if there's a crack inside the garbage disposal. Cracks are part of the normal wear and tear of a disposal so they're fairly common to see in older disposals.If your disposal has a crack, the only solution is to purchase a new one. For more information, CLICK HERE to read our article: Garbage Disposal Leaking From Bottom: Here's What to Do. Persistent OdorWhen your garbage disposal smells, there's a good chance that food waste is trapped inside. But before jumping to the worst case scenario, try cleaning it with the techniques in our article: How to Keep Your Garbage Disposal Healthy. Click HERE to read.Never use chemical cleaners in your garbage disposal, as they can damage the disposal's blades and components.If nothing seems to work, there's probably food trapped inside. At this point you have 2 options. You can call a plumber and have him disassemble the disposal to remove the food; or you can simply purchase a new garbage disposal.If your garbage disposal is over 10 years old, it's generally more cost effective to simply replace your old unit.Extended Grind TimeWhen your garbage disposal is operating in peak form it shouldn't take more than a couple of seconds to grind your food waste. But as they age, it's not uncommon for your disposal to take longer to grind the same amount of waste. This video shows how a garbage disposal works: There are two main reasons garbage disposals take longer to grind down food.Motor Over time, the disposal's motor begins to weaken and struggles to handle the same workload that it was once capable of grinding. When this is the problem, your best is to purchase a new garbage disposal.Grind RingThe other cause could be the grind ring. Many people think that garbage disposals have blades, but actually they have impellers that force the food (with centrical force) into the grind ring. If the grind ring becomes dull or full of food waste, the garbage disposal will struggle to grind the waste.First, try cleaning the grind ring, and if that doesn't speed things up, you should probably replace the unit. In many cases these parts can be replaced by a professional, but a new garbage disposal is more cost effective.Unusual NoisesGarbage disposals can make some unusual noises. Before you start worrying you should first check for the obvious. Did a foriegn object, such as a spoon, fall inside the unit when you weren't looking?Use a flashlight and a set of tongs to check inside and fish the item out. NEVER put your hand inside a garbage disposal.MotorIf you turn on your disposal and all you hear is a loud humming noise, without any grinding action, there's a good chance the motor has burned out.The fact that you hear humming means that the disposal is receiving electricity, but it's unable to grind food waste since the motor is no longer working.Motors don't always die quietly. If you hear a shrill noise, it could be that your motor is dying. Although, you can replace the motor, in most cases it'll be cheaper to purchase a new garbage disposal.Out of AlignmentIf you hear a screeching noise, it's possible that the internal components are out of alignment. In many cases, this problem can be solved by calling a plumber to adjust the alignment.Loose ImpellersIf the impellers become loose, the garbage disposal will make a horrible clanking sound. The disposal will need to be taken apart in order to repair or replace the impellers and that should only be done by a plumber. If this is your problem, you should ask your plumber if he recommends repairing or replacing the unit. Frequent ClogsIf you are feeding your garbage disposal in small quanities, yet it's still clogging regularly, there are 2 common reasons. Undersized UnitIf your garbage disposal isn't able to meet the needs of your family it probably just doesn't have enough horsepower. When determining the correct size disposal for your household the primary measurement is the amount of horsepower it'll deliver.The more horse power it has, the more food it'll be able to break down each time it's used. If this is your problem, you can replace the disposal with a unit that has more horse power. Dull Grind RingThe grind ring is often referred to as blades, but in actuality the impellers force the food against the grind ring which is full of "sharp teeth" to grind the food.When the grind ring isn't able to break down the food waste into small particles, larger pieces can either create a clog in the disposal or move into the sink drainpipe and cause a clog.Never use chemicals in your garbage disposal to try to break up a clog. Try to reset the unit with the disposal's reset switch, and if that doesn't work insert an allen wrench into the hex slot on the bottom of the unit, and do a full turn each direction. Our article on How To Unclog a Garbage Disposal goes into more detail.No PowerWhen your garbage disposal won't start and isn't making any noise at all, the first thing you should do is press the reset button on the bottom of the unit.If it still isn't working, check your household circuit breakers to see if the breaker the disposal is on was tripped. Once you've ruled out a tripped breaker, the problem is most likely the motor.You should contact a plumber to have him check things out and install a new garbage disposal if necessary.Kitchen RenovationIf you're planning on remodeling your kitchen or simply replacing your sink, you should seriously consider updating your garbage disposal.There's nothing worse that spending thousands of dollars to build a beautiful kitchen and then use your old, loud garbage disposal. It kind of ruins the vibe.If your disposal is realitively new, it'll likely work nicely in your new kitchen. But older models are prone to problems, and if yours hasn't started to cause you trouble, it most likely will soon.Unless you're a DYI'er, you'll already have a professional working in your kitchen. It's often more cost efficient to replace it when you're doing renovations, than to wait for the disposal to break down.