There are primarily three things that will decide bulb life, voltage, time, and vibration. The bulb will have a certain lifetime, this is just the physics of it. Over-voltage will also drastically shorten bulb life, and vibration can easily cause premature failure due to stress on the filament.
Some suggestions, use LED's for the bulbs. This may require installing load resistors to prevent messages on the dash display and/or hyperflash on turn signals, so isn't 100% Plug-n-Play. These will be have longer life by design, and are much less susceptible to vibration.
Another possible idea, if LED's are too much work, is to use halogen bulbs. These typically have sturdier filaments and the "halogen" aspect prevents normal filament wear by re-depositing the boiled away filament material back onto the filament.