Your Hummer starter is designed to get your engine running in all kinds of weather conditions, but over time, even the most well-engineered of starters will start to deteriorate. Some signs of a worn out starter: You turn the ignition key to the "start" position and nothing happens, or there is just the sound of clicking. The starter may crank very slowly. If you have ruled out all other possibilities, such as a faulty battery or solenoid, then consider changing the entire Hummer starter system. Other reasons for a non-starting car: dirty or loose battery cables, or a faulty charging system. If you have eliminated all the other options, and your car is still not starting (and your Hummer starter has over 50,000 miles on it) then replace it with a new Hummer starter as a preventative maintenance measure. If one part of a starter is failing - usually the drive or 'Bendix' will wear out first - then the other parts are probably due for failure as well. For that reason, it's a good idea to replace the Hummer starter as an entire unit, instead of repairing the individual components. When you do replace your Hummer starter, check your electrical system to prevent further problems with starting your car.