GENUINE GM 24 TOOTH RELUCTOR WHEEL -12559353

GM LS ENGINES feature a toothed reluctor wheel (also called a tone wheel or tone ring), which is press-fit onto the rear of the crankshaft. This toothed wheel is used by the crankshaft position sensor for ignition timing

SENSOR: 24x wheels are detected by a black sensor, while 58x use a grey sensor. This sensor is located at the back of the block, near the oil pan, on the drivers side of the engine, just above the starter motor.