GMC C15 Oil, Fluid, and Additive

General information on engine oil, including selection recommendations.

Lake Speed Jr., from Driven Racing Oil, answers the question "what viscosity grade should I run". He explains what viscosity really means and some key factors to keep in mind when selecting the right viscosity grade for your engine and application.

Lake Speed Jr., from Driven Racing Oil, discusses how to choose the motor oil with the right amount of zinc for your vehicle's unique needs.

Tim M. has tried to stay true to the vintage route, but sometimes, exceptions must be made. For example, the original oiling system's paper element and canister are functional, but an upgraded system will be more reliable.

Learn how to repair an oil line leak using steel braided hose and AN fittings. See how to cut the hose, measure angles, apply fittings and install fuel lines back into your car.

Read how to install rear drop spring to lower a 1969 C10 pickup. Follow these steps for a smooth installation.

Some key considerations for designing your own fuel system. We cover fuel pressure and volume, fuel pressure regulators and fuel lines.

In this Tech Tip, John offers up a couple solutions to a somewhat common problem of fuel expansion on the older vehicles.

Learn about GM alternator identification in our guide. We cover GM 3 wire alternators, 1 wire alternators, and externally regulated so you know what to choose.

Professional insight on some useful crate engine tools that will improve your engine building experience.