Autolite 147 Spark Plug

Autolite 147 Copper Resistor Spark Plug

Autolite 147 is a copper resistor spark plug built for OE-style replacement in older Chevrolet, GMC, Pontiac, and Oldsmobile applications. It is specified with a 0.034 in. pre-gap, 5,000 ohm resistance, and a tapered seat for direct-fit service where the original plug calls for this configuration.

Key Features

• Copper center electrode core for reliable ignition performance
• Nickel center and ground electrode tip materials
• 5,000 ohm resistor design to help control electrical noise
• 0.034 in. pre-gap, 14 mm thread diameter, and 0.431 in. reach
• Tapered ground electrode tip design with a single ground electrode
• Ceramic short insulator and stud-style electrical terminal
• 5/8 in. hex size for standard spark plug service tools

Product Details

The Autolite Copper Resistor Spark Plug line focuses on OE form, fit, and function for a wide range of domestic and import vehicles. Part number 147 uses a copper core to support quick starts and smooth acceleration, while the resistor construction helps reduce interference in ignition systems. This part cross-references Monroe Shocks & Struts (e.g., 35, 5613324) for the same application.

Compatible With 1970 Chevrolet Blazer, 1970 Chevrolet C10 Suburban, 1970 Chevrolet C20 Suburban, 1970 Chevrolet K10 Suburban, 1970 Chevrolet K20 Suburban, 1970 GMC G15/G1500 Van, 1970 GMC G25/G2500 Van, 1970 GMC G35/G3500 Van, 1970 GMC Jimmy, 1970 Pontiac Firebird, 1970 Pontiac LeMans, 1972-1974 Chevrolet Blazer, 1972-1974 Chevrolet C10 Suburban, 1972-1974 Chevrolet C20 Suburban, 1972-1974 Chevrolet K10 Suburban, 1972-1974 Chevrolet K20 Suburban, 1972-1974 GMC G15/G1500 Van, 1972-1974 GMC G25/G2500 Van, 1972-1974 GMC G35/G3500 Van, 1972-1974 GMC Jimmy, 1972-1974 Pontiac Firebird, 1972-1974 Pontiac LeMans, 1974 Pontiac Parisienne, 1972-1973 Chevrolet El Camino, 1975 Chevrolet C10, 1975 Chevrolet C10 Suburban, 1975 Chevrolet C20, 1975 Chevrolet C30, 1975 Chevrolet El Camino, 1975 Chevrolet G10, 1975 Chevrolet G20, 1975 Chevrolet K10, 1975 Chevrolet K10 Suburban, 1975 Chevrolet K20, 1975 Chevrolet K5 Blazer, 1975 GMC G15, 1975 GMC Jimmy, 1975 Oldsmobile Cutlass, 1975 Oldsmobile Cutlass Supreme, 1975 Oldsmobile Omega, 1975 Pontiac Firebird, 1975 Pontiac Grand LeMans, 1975 Pontiac LeMans, and 1976 Chevrolet P30. The fitment notes include OE-style replacement references for OEM part number 687 and original gap specifications on listed applications.

Common Service Uses

• Hard starting caused by worn or fouled spark plugs
• Rough idle from inconsistent spark delivery
• Misfire complaints under load or during acceleration
• Ignition noise concerns in resistor-equipped systems
• Routine tune-up replacement on classic Chevrolet, GMC, Pontiac, and Oldsmobile engines

Installation Notes

Verify thread diameter, reach, seat type, and gap before installation. Autolite 147 is a 14 mm, tapered-seat spark plug with a 0.431 in. reach and 0.034 in. pre-gap; confirm the engine specification against the vehicle service manual before final torque and installation. Use the correct 5/8 in. spark plug socket and inspect ignition wires, cap, and coil condition during service.

Quality Assurance

Autolite supplies ignition products to the automotive aftermarket and OE channels, and this copper resistor spark plug is built to OE-style dimensions and service requirements for the listed applications. Part number 147 is engineered for direct replacement use where the original plug specification matches the fitment data above.