Originally Posted by labman
I would think if there was a problem with the starter, it would have gotten worse over 5 years. Work on the connections, making they are clean and tight both from the battery to the starter, and from the battery to the engine. always disconnect the negative terminal to the battery before working on the positive cable.
The connections inside the solenoid could be bad too, but harder to check. You could have somebody turn the engine over while you checked the voltage at both solenoid terminals. If it drops, the solenoid is bad and should be replaced.