Are there manual hubs available for a 2002 Chevrolet 4 wheel drive pickup?
No, the 2002 Chevrolet Silverado/Sierra 1500, 2500, and 3500 HD pickups did not offer a factory option for manual locking hubs. They came standard with automatic locking hubs integrated into the front axle. You cannot easily convert to manual hubs. Aftermarket manual locking hubs are not available for these trucks.