Turns, Lane Changes, Passing and Tailgaters

Key points

1. Signal at least 100 feet before a turn where the limit is 45 mph or less, and 300 feet where it is higher.

   Source: Handbook p. 43

   “Iowa law requires you to signal at least 100 feet before a turn if the speed limit is 45 mph or less and if the speed limit is faster than 45 mph, you must signal at least 300 feet before you turn.”
   Iowa Driver's Manual, Handbook p. 43

2. You may turn left on red from a one way street onto another one way street.

   Source: Handbook p. 43

   “You may also make a left turn at a red light if you are turning from the left lane of a one-way street onto another one-way street.”
   Iowa Driver's Manual, Handbook p. 43

3. Change lanes only one lane at a time.

   Source: Handbook p. 44

   “Only change lanes one lane at a time.”
   Iowa Driver's Manual, Handbook p. 44

4. Do not pass within 100 feet of an intersection.

   Source: Handbook p. 46

   “Do not pass within 100 feet of an intersection.”
   Iowa Driver's Manual, Handbook p. 46

5. Do not pass within 100 feet of a railroad crossing.

   Source: Handbook p. 46

   “Do not pass within 100 feet of a railroad crossing.”
   Iowa Driver's Manual, Handbook p. 46

6. Return after passing when you see the front of the passed car in your mirror.

   Source: Handbook p. 45

   “When you see the front of the passed car in the rearview mirror and your vehicle is well clear, signal intent, gently and slowly move back to the original lane”
   Iowa Driver's Manual, Handbook p. 45

7. If tailgated, move slightly right and signal early for turns, stops or lane changes.

   Source: Handbook p. 48

   “If you are being tailgated, move slightly to the right and give the tailgater a better view of what is ahead and signal early for turns, stops, or lane changes.”
   Iowa Driver's Manual, Handbook p. 48

8. If another driver is driving aggressively, slow down or pull over to avoid them.

   Source: Handbook p. 47

   “If another driver is showing signs of aggressive driving, slow down or pull over to avoid them.”
   Iowa Driver's Manual, Handbook p. 47

Numbers to know

3 questions from the Iowa practice test

1. 1. Before moving into another lane, which sequence best follows Iowa's lane-change guidance?

   1. Signal, check the blind spot, then look only at the rearview mirror
   2. Brake sharply in the current lane before steering over
   3. Move across two lanes quickly before another vehicle can enter
   4. Check traffic and space, signal, inspect mirrors and the blind spot, then move one lane
   Show answer

   Check traffic and space, signal, inspect mirrors and the blind spot, then move one lane. A safe lane change is a planned, single-lane movement. First confirm that the target lane has room and yield to traffic already there. Signal to communicate, use the rearview and side mirrors, and look over the shoulder toward the lane you intend to enter. The choice “Signal, check the blind spot, then look only at the rearview mirror” omits a proper blind-spot check, while the choice “Move across two lanes quickly before another vehicle can enter” creates unnecessary risk by crossing two lanes at once. Keep the wheel straight during the shoulder check, then move over smoothly without unnecessary braking. The practical cue is to check the lane, signal, mirror, shoulder, and only then steer.

2. 2. If another vehicle is tailgating you, what adjustment can give that driver a better view ahead?

   1. Move slightly to the right and create more space ahead
   2. Brake sharply whenever the vehicle gets close
   3. Speed up until you are beyond the posted limit
   4. Turn off your lights so the other driver backs away
   Show answer

   Move slightly to the right and create more space ahead. When a driver follows too closely, move slightly to the right to give that driver a better view of the road ahead. Signal early for turns, stops, or lane changes, and if possible slow enough to encourage the other driver to pass. Sudden braking can cause a rear-end crash, and speeding beyond the limit trades one hazard for another. Turning off lights reduces visibility. Keep your attention on the roadway, leave room in front of your own vehicle, and pull out of the traffic flow if the tailgating continues and a safe opportunity exists.

3. 3. How should you respond when another driver shows signs of aggressive driving toward you?

   1. Make eye contact and challenge the driver
   2. Slow down or pull over to avoid the driver
   3. Race ahead to prevent the driver from passing
   4. Brake suddenly to make the driver stop
   Show answer

   Slow down or pull over to avoid the driver. If another driver is showing signs of aggression, slow down or pull over to avoid that person. If the driving is dangerous enough to worry you, try to leave the roadway by turning right or taking the next exit when it is safe. Eye contact, racing, and sudden braking can escalate the encounter or reduce your control. Keep your attention on finding distance and an escape route rather than proving a point. Do not stop in an exposed travel lane; choose a safe place where the aggressive driver can continue away from you.

Source: the Iowa Driver's Manual, Chapter 4: Turning, Changing Lanes and Passing. This lesson is a plain English summary, not the law itself; where it differs, the manual and the statute govern. Last checked 2026-09-27.