What is center of gravity (CoG) in load planning?

The center of gravity is the point where a load's weight balances. Its position along the trailer determines how weight splits across the steer, drive, and trailer axles.

The center of gravity (CoG) of a load is the single point where its weight is balanced in every direction. In load planning the CoG's position along the length of the trailer is what matters most: it determines how the total weight divides across the steer, drive, and trailer axle groups.

Why it drives compliance

A load can weigh exactly 80,000 lb and still be illegal because its CoG sits too far forward (overloading the drive tandem) or too far back (overloading the trailer tandem). Moving the CoG — by re-positioning cargo or sliding the tandem — is how you rebalance axle weights without changing the total.

LoadLegit computes the CoG from your packed load and predicts each axle weight, then tells you the exact slide to bring an overloaded axle back within limits.

Check a real load in secondsLoadLegit turns axle weights into a pass/fail compliance verdict — federal Bridge Formula plus verified state and Canadian rules — and issues a shareable certificate. Try it free →

What is axle weight?Axle weight is the portion of a vehicle's total weight carried by a single axle or axle group — the number weigh stations and the Bridge Formula regulate.What is the steer axle?The steer axle is the front, steered axle of a truck. Federally it may carry up to 20,000 lb, but tires and the front-axle rating usually limit it to 12,000–13,200 lb.What is a tandem axle?A tandem axle is two axles spaced close together (typically 40–96 inches) that share a load as one group. The US federal tandem limit is 34,000 lb.