Rollover Prevention and Load Stability
What this domain tests
This domain tests center of gravity, speed in curves, load securement, weight distribution, rearward amplification, and smooth evasive action to prevent rollover.
Core rules
- A high center of gravity increases rollover risk. Load heavy items low and centered, and secure them against shifting.
- Rollover often happens in curves or during abrupt avoidance. Slow before the curve, not in it.
- Rearward amplification makes the last trailer swing widest; avoid sudden lane changes and hard steering.
- Check cargo securement and weight limits; an overloaded or shifted load reduces stability and braking.
- If a blowout or obstacle forces evasive action, steer smoothly and avoid hard braking in a curve.
Worked example
A curve is posted at 35 mph. You enter at 45 mph with a high, loaded trailer. The trailer's center of gravity leans outward, and the rear tires may lift. The correct action is to slow before the curve, select a safe speed, and steer smoothly. The reasoning: rollover risk rises with speed and center-of-gravity height; braking hard mid-curve can also upset the combination.
Traps that cost marks
- Entering a curve too fast with a high load.
- Braking hard in the middle of a curve.
- Failing to secure or distribute cargo.
- Making abrupt lane changes with doubles or triples.