Space Management and Speed Control
What the exam tests
Space Management and Speed Control tests following distance, speed selection, and cushion around the whole vehicle. The exam expects you to adjust space and speed before a problem develops.
Core rules
- Count following time from when the vehicle ahead passes a fixed object until your front bumper reaches it.
- Use at least one second per 10 feet of vehicle length below 40 mph; add one second above 40 mph. A 60-foot combination at 55 mph needs about seven seconds.
- Increase space for rain, snow, darkness, heavy loads, downgrades, and poor brakes.
- Control speed before a curve or downgrade; use a lower gear and engine braking. Do not ride the service brake until it fades.
- Keep side and rear space; avoid lingering beside other vehicles.
Worked example
At 55 mph in a 60-foot truck, the base is six seconds for length, plus one second because speed is over 40 mph, so seven seconds. In rain, add more because stopping distance rises and visibility falls. The correct response is to back off early, not to wait until the gap closes.
Traps that cost marks
Counting only two seconds as in a car, looking only at the bumper ahead, braking late on a downgrade, and matching speed to the posted limit rather than conditions. Space management is judged by what you do before the hazard, not after it.
Key idea
A safe gap is one you can defend with time, not one you hope will open.