Changing lanes safely is important
to avoid side collisions

Remember SMOG:
Mirror (side mirror)
Over your shoulder

This is the order of things you should do when lane changing.
Some people say "MSMOG" for rear view mirror check first.

In my opinion, communicating with your signal is at least as important, and possibly more so than checking the mirror for cars behind first, though both need to be done, maybe simultaneously, before changing lanes.

Remember that what happens in traffic happens quickly because of the speed of traffic. For this reason, it is important to do each part of SMOG within about 2 seconds of each other.

If you let 5-10 seconds laps between turning your signal on and checking your mirror and over your shoulder, the driver that was leaving space behind you for you to come in, will decide it is taking you too long to come over, not knowing if you will come over, he will want to speed up and get around you.

If you let even 5 seconds laps between checking over your shoulder and coming into the next lane, a vehicle could easily have time to come into your blind spot to pass you.

When driving in traffic remember to choose carefully but act quickly.

It used to be that new drivers were taught to adjust the side mirror correctly, you were to see just a little of the side of your vehicle. While you see more directly beside your vehicle with this adjustment, it is better to see more of the lane next to yours. To do this, the mirrors should be out to where you don't see your vehicle while driving, but you will see a little of the vehicle when you lean toward the mirror.

Some people say this eliminates all of the blind spot, therefore you don't need to look over your shoulder when changing lanes. This is false. It just lessens the blind spot, but there could still be a vehicle you didn't see coming up behind you. Looking over your shoulder is still very important.
If you have trouble turning your head, lean your body forward a little so you can turn more of your body, not just your neck.

For vehicle blind spots click here.

For correct side view mirror adjustment click here

Techniques for changing lanes safely:

Know what is happening ahead of you and behind you.
You may need to speed up for the car behind,
but slow down for the car ahead.

Keep two lanes open.
If you have two or more lanes next to you in the direction you are changing lanes, make sure the second lane over is clear.

If a vehicle is coming near you in that lane, they may also make a lane change at the same time you do. If you can't let them get ahead or behind, watch their tires!

Stay at the speed of the traffic when changing lanes.
Many inexperienced drivers brake to do a lane change.

You only brake or slow down on a lane change if they are doing that
ahead of you or a stop signal is ahead.

Keep your steering wheel steady.
It is easy to drift the other direction when you look over your shoulder for vehicles in the lane you are coming into. A firm grip on the steering wheel will help prevent this from happening.

"Glide" into the next lane without turning the steering wheel.
Remember a lane change is not a turn. You should be able to come into the adjacent lane without the steering wheel appearing to move at all.

It takes such a tiny amount of moving the wheel to glide your car left or right that your steering wheel should stay virtually straight on a lane change.

The exception to this is when you are coming slow into a tight space.(usually a traffic jam)

Watch for objects smaller than cars or trucks.
Always remember a space that a car or truck couldn't fit, may fit a bike, motorcycle or pedestrian. They are also harder to see even on wide streets, therefore keep in mind when checking your blind spots, to watch for the smaller vehicles as well as large, even in a small spaces such as a turn lane often has.

Keep your eyes on any parked vehicle you pass when lane changing.
It is best to avoid coming into a lane next to a parked car, but some streets are so busy with many parked vehicles, you may not be able to avoid it.

In that case, watch the tires of the parked vehicle for movement into the travel lane, as well as the side for opening doors.

Avoid intersections on lane changes
It may not be against the law to make a lane change in an intersection in the state or place you live,

however, it isn't safe because someone could be turning into the lane at the same you change lanes.

It is also more likely that pedestrians will be crossing at an intersection when you don't see them.

* Remember to watch for intersections that have no signs or signals going your direction. Those are the hardest to see, but vehicles and pedestrians could still be in them.

It is important to be proficient at changing lanes
when you take your DMV road test.

This "Get Ready to Pass" video demonstates everything the drive tester will look for in lane changes and many other driving skills you will be tested on to get your license.

Learn How To Pass Your Road Test

Spacing on a lane change

You should always leave about two car lengths ahead and behind when changing lanes, no matter how slow you are going, and two to three seconds or three to four car lengths at freeway speed.

The truck on the left is merging in front of me with barely two car lengths or almost 1 second at 55 mph. At 25 mph that would leave safe braking distance, but not at freeway speed.

The car on the right is leaving roughly two to three car lengths or almost 2 seconds at 55 mph., this is the least amount of space you want for comfortable merging on the freeway.

The truck on the left is merging in front of me with barely two car lengths or almost 1 second at 55 mph. At 25 mph that would leave safe braking distance, but not at freeway speed.

The car on the right is leaving roughly two to three car lengths or almost 2 seconds at 55 mph., this is the least amount of space you want for comfortable merging on the freeway.

Using mirrors while changing lanes

The first mirror you should check before a lane change is your rear view mirror on your windshield.
Some instructors say to see the headlights of the vehicle behind in the lane you are coming into. this usually gives you enough space to come in, but if you just barely see his headlights, it won't give that driver much room if you suddenly had to brake, and it won't feel too comfortable for either of you.

I tell my student see some ground between you and the car behind. This gives extra space for the unexpected. And it feels a lot safer seeing ground, not just lights.

Looking at the cars in the right lane in the mirror in the pictures, the car in the left picture shows plenty of ground.
This will give you about 3-4 comfortable car lengths as you come into his lane. Giving the driver plenty of room to adjust his speed if needed.

In the picture to the right, you can just see the headlights of the vehicle to the right, but no ground.
This gives you barely 2 comfortable car lengths as you come in front of him. Remember, at 55 mph or more you want at least 3 car lengths. The driver would have to do some quick braking to avoid hitting you if you had to suddenly slow down.

If the lane change was in the city at 20-25 mph,they could brake much quicker, making it not as hazardous, although you will always be safer with more distance.

Checking the side mirrors is important as well. If your side view mirrors are adjusted correctly, you will have a very minimal blind spot to the sides of your vehicle.

Also remember, the further to the outer edge of the side mirror you see a vehicle, the closer it is to you, and the further to the center it is, the farther away it is from you.

The pictures to the left show a vehicle where you should see it in your side mirror when you have enough space to move into their lane, that is in the center of your mirror, a little closer in to the side than out.

The pictures on the right show the vehicles closer to the outside of your mirror, leaving probably not much more than one second in front of them if you came into their lane (way too close at freeway speed).

For correct side view mirror adjustment click here

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More to come on changing lanes

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