Vehicle Service Manuals: OEM vs. DIY Aftermarket

So you’ve decided to learn more about your vehicle, and are looking for the best manual you can find. But where do you start? You’d like to get an original factory manual – but is a less expensive aftermarket DIY manual from Haynes, Chilton, or Clymer exactly what you need? The Motor Bookstore examines the upside of each.

OEM/factory manuals

OEM, or “original equipment manufacturer” manuals, offers the most information you can find about your vehicle. They’re written by the company that built the vehicle and are aimed at professional technicians and advanced mechanics. Different types of OEM manuals can include service manuals, wiring manuals, unit repair manuals and owner’s manuals. These manuals are usually hundreds and even thousands of pages. While they can be expensive and harder to find for older vehicles, and the sheer amount of information can be overwhelming for newcomers, they’re an invaluable resource to have.

DIY/aftermarket manuals

Chilton, Haynes and Clymer are often referred to as “do it yourself” or “aftermarket” manuals. These books usually cover one or two vehicles spanning multiple years. (For example, one Haynes manual covers the Honda Accord from 2003-2012 and the Honda Crosstour from 2010-2014.) As a result, there is typically less information about each specific vehicle, but they do include additional instructions, photographs and illustrations for novices.

Chilton has been publishing automotive magazines and manuals for more than 100 years, and is known for their Chilton Total Care series. Haynes has been around for almost 60 years and publishes automotive manuals, motorcycle manuals and techbooks. Manuals from each are typically a few hundred pages and cover various maintenance and repair procedures. Chilton manuals also include engine torque specifications for those looking to rebuild engines. Clymer manuals focus on power sport vehicles such as motorcycles, ATVs and snowmobiles. Their big selling point is that each machine is completely disassembled and reassembled during the writing process, resulting in more detailed instructions.

Final thoughts

If you’re a novice mechanic, a DIY manual from Chilton, Haynes or Clymer is a great starting point, and their instructions and diagrams will be helpful on early projects. More experienced mechanics will want to make the additional investment in an OEM manual aimed at their specific vehicle.