Look for slow-moving vehicles and adjust your speed accordingly.
Keep an eye out for big rigs and small, old-fashioned cars, which often have less power on steep grades.
Be wary of oversized trucks and older vehicles when you're entering traffic; these vehicles tend to take longer to reach the speed limit so you don't want to run into the back of them in your haste to merge.
Slow down or stop for livestock on roadways. It is illegal to stampede or frighten them.