Older drivers represent the fastest-growing segment of the driving population and are at increased risk of traffic crashes. Therefore, effective interventions are essential to maintain their driving safety. Drawing on self-determination theory, this study investigates older drivers' motivational needs for training participation and develops a psychologically grounded driving training program. A driving simulator experiment was conducted with 20 older drivers, with 20 younger drivers serving as a comparison group. All participants completed three driving tests: a baseline test (T1), an immediate post-training test (T2) and a 3-day post-training test (T3). Training effectiveness was evaluated using Kirkpatrick's four-level model. Results showed that the training significantly improved older drivers' traffic-related knowledge and driving performance. Moreover, older drivers demonstrated further performance gains at T3 relative to T2, particularly in reducing hard deceleration, hard braking and speeding events. These findings enhance understanding of older drivers' learning processes and provide empirical support for targeted interventions.