Large trucks have numerous blind spots, which are areas truck drivers can't see using their mirrors alone. For instance, the areas directly in front of and behind and on the right side of the truck are particularly hard to see when operating a big rig. Other vehicles must steer clear of these blind spots, otherwise they run the risk of being involved in a collision.
While you may think you're being overly careful, passing a truck too slowly can actually have the opposite effect. When passing a truck on the highway be sure to do so quickly (while also obeying the speed limit) and make sure your vehicle is a safe distance away from the truck lane. It's not uncommon for large trucks to drive at a slower pace, so get used to safe passing if you spend a lot of time on the highway.
It's recommended that passenger vehicles maintain a distance of at least four seconds when driving around trucks. If a truck stops suddenly or makes an unexpected maneuver you want to make sure you have ample time to react. This is especially important in the event a truck has a tower blowout, which would result in the driver losing control of the vehicle.