The ignition distributor provides the high voltage current produced by the secondary coil to the correct spark plugs in the correct firing order and at the correct time. Eventually they wear out over time like the spark plugs and wires resulting in poor electrical insulation which causes engine problems in the future therefore making it important to be part of the regular tune-up maintenance. If you are experiencing abnormal shaking, the car does not start, engine misfiring, excessive or unusual engine noises, you might have problems with your ignition distributor. It is a device in the ignition system located near the coil of your car's ignition system. Fits the following vehicles: 1996-1999 C1500 5.0L (305cid) 1996-1999 C1500 5.7L (350cid) 1996-1999 C1500 Suburban 5.7L (350cid) 1996-1998 C2500 5.0L (305cid) 1996-2000 C2500 5.7L (350cid) 1996-1999 C2500 Suburban 5.7L (350cid) 1996-2000 C3500 5.7L (350cid) 1996-2002 Express 1500 5.0L (305cid) 1996-2002 Express 1500 5.7L (350cid) 1996-2002 Express 2500 5.0L (305cid) 1996-2002 Express 2500 5.7L (350cid) 1996-2002 Express 3500 5.7L (350cid) 1996-1999 K1500 5.0L (305cid) 1996-1999 K1500 5.7L (350cid) 1996-1999 K1500 Suburban 5.7L (350cid) 1997-1998 K2500 5.0L (305cid) 1996-2000 K2500 5.7L (350cid) 1996-1999 K2500 Suburban 5.7L (350cid) 1996-2000 K3500 5.7L (350cid) 1996-1999 P30 5.7L (350cid) 1996-2000 Tahoe 5.7L (350cid) 2000-2002 W3500 Tiltmaster 5.7L (350cid) 1998-2002 W4500 Tiltmaster 5.7L (350cid) 1996-1999 C1500 5.0L (305cid) 1996-1999 C1500 5.7L (350cid) 1996-1999 C1500 Suburban 5.7L (350cid) 1996-1999 C2500 5.0L (305cid) 1996-2000 C2500 5.7L (350cid) 1999-1996 C2500 Suburban 5.7L (350cid) 1996-2000 C3500 5.7L (350cid) 1996-1999 K1500 5.0L (305cid) 1996-1999 K1500 5.7L (350cid) 1996-1999 K1500 Suburban 5.7L (350cid) 1998 K2500 5.0L (305cid) 1996-2000 K2500 5.7L (350cid) 1996-1999 K2500 Suburban 5.7L (350cid) 1996-2000 K3500 5.7L (350cid) 1996-1999 P3500 5.7L (350cid) 1996-2002 Savana 1500 5.0L (305cid) 1996