When passing a truck, first check to your front and rear, and move into the passing lane only if it is clear and you are in a legal passing zone. Let the truck driver know you are passing by blinking your headlights, especially at night. The driver will make it easier for you by staying to the far side of the lane.
On a level highway, it takes only three to five seconds longer to pass a truck than a car. On an upgrade, a truck often loses speed, so it is easier to pass than a car. On a downgrade, the truck's momentum will cause it to go faster, so you may need to increase your speed.
Complete your pass as quickly as possible, and don't stay alongside the other vehicle.
If the driver blinks his lights after you pass, it's a signal that it is clear to pull back in. Be sure to move back only when you can see the front of the truck in your rear-view mirror. After you pass a truck, maintain your speed.
When a truck passes you, you can help the truck driver by keeping to the far side of your lane. You'll make it easier for the truck driver if you reduce your speed slightly. In any event, do not speed up while the truck is passing. After passing, the truck driver will signal to let you know that the truck will be returning to your lane.
When you meet a truck coming from the opposite direction, keep as far as possible to the side to avoid a sideswipe crash and to reduce the wind turbulence between the two vehicles. Remember that turbulence pushes the vehicles apart; it does not draw them together.