About these guides

Serious Load explains trucks, trailers and cars the way a patient, experienced friend would: how the parts work, why the rules exist, and what the numbers mean. The guides are written for curious drivers, new and future truckers, and anyone who has ever wondered how an 80,000-pound rig stops.

How we write these guides

• Rules are described in general terms. Federal trucking regulations come from the Federal Motor Carrier Safety Administration (FMCSA), and states add their own. We link to official sources instead of pretending to replace them.
• Nothing here is legal, career or mechanical advice for your specific situation. Your carrier, your CDL school, your state DMV and your vehicle's manual have the final word.
• We avoid hype. When we are not sure of a number, we leave it out.

Found a mistake?

Regulations and records change. If something here is out of date, tell us through our YouTube channel and we will fix it.