What does the bump sign mean?

This sign is posted on a road you are driving with a full load of passengers. What is the right response?

Slow before you get there so the suspension is settled as you cross

Hitting uneven pavement at speed unloads the tires for a moment, and a tire with no weight on it has no grip for steering or braking. Slowing before the bump rather than on it keeps the car settled and keeps whatever is in the trunk where you put it.

This sign is posted on a road you are driving at speed. Why does it matter beyond comfort?

The wheels can go light as you cross, so grip for braking and steering drops just then

Weight coming off the wheels means less grip for braking or steering at the very moment the vehicle is unsettled. Slowing before you reach it keeps the suspension in control, and it protects both the vehicle and anything loose in the back.

This sign warns about what is on the road surface just ahead. What is the right response?

Slow down before you reach it and keep the steering straight

Hitting uneven pavement at speed unsettles the car at the moment you have least grip to correct it, and braking or turning at the same time makes that worse. Get the speed off first, then cross it with the wheels straight. Leave room for whoever is behind you, because a motorcycle or a loaded vehicle needs even more.

This sign appears just before a section of road that has been patched and repatched. What is the right response?

Slow down before you reach it and keep both hands on the wheel

A vehicle crossing a bump at speed goes light on its springs, and a light vehicle steers and brakes badly for the moment it takes to settle. Slowing beforehand keeps the tires loaded and the car pointing where you aimed it. Braking on the bump itself is what unsettles it most.

You are hauling a load held by chains and binders when you see this sign.

Slow before it, and check the tiedowns at your next safe stop

A jolt lets a load lift for an instant, and chains that were tight can be slack once it settles again. That is why securement is checked before you leave and rechecked along the way rather than once. Slowing before the bump keeps the shock small in the first place.

This sign appears on an industrial road you are using with a strapped flatbed load.

Slow right down, since a jolt can loosen straps that were tight when you left

A hard bump throws the load up off the deck for an instant, and tie downs that were tight before can be slack afterwards. Speed decides how violent that instant is, which makes slowing the whole answer. Taking a bump on one side only twists the vehicle and works the load sideways as well as upward.