Your exam
30 questions. 21 correct to pass — you may miss 9.
Following distance — two rules, not one
| Your speed | Minimum gap |
|---|---|
| Under 30 mph | 2 seconds |
| 30 mph and above | 4 seconds |
| Any speed, if you are a new driver | 4 seconds |
Most states teach a single figure. Texas gives two, and applying the low one at highway speed halves the gap you actually need. Add more in rain, fog or heavy traffic.
Move Over — also two rules
An emergency medical vehicle, law enforcement vehicle, fire truck or tow truck stopped with lights on. You must either move out of the lane closest to it, or:
| Posted limit | Slow to |
|---|---|
| 25 mph or more | 20 mph below the limit |
| Under 25 mph | less than 5 mph |
Subtracting 20 from a 20 mph limit gives nothing, which is exactly why the second rule exists. Slowing is not a courtesy here — it is the alternative the law names when you cannot change lanes.
Alcohol
| Driver | Limit |
|---|---|
| 21 or over | 0.08 |
| Under 21 (a "minor" in Texas) | any detectable amount |
There is no threshold to stay under if you are a minor. Refusing a breath or blood test suspends your driving privilege on its own, whatever happens to the criminal case — that is implied consent.
Distances
- 15 feet — closest you may park or stand to a fire hydrant.
- 20 feet — from a crosswalk at an intersection, and from the driveway entrance to a fire station.
- 30 feet — on the approach to any flashing signal, stop sign, yield sign or traffic control signal at the side of the road. The largest of the three, because a car parked closer hides the sign from drivers approaching it.
- 1,000 feet — if people or vehicles cannot be seen clearly at that distance, headlights are required whatever the clock says.
The prohibitions cover standing and idling, not just parking. Staying in the driver's seat does not make it legal.
Headlights
Required from 30 minutes after sunset until 30 minutes before sunrise, and any time visibility drops below 1,000 feet — fog, heavy rain, sleet, snow or dust.
Parking on an unlighted highway at night: leave your parking lights or low beams on. An unlit vehicle at the edge of a dark road is invisible until it is too late.
School buses
Alternately flashing red lights: stop, from either direction. You may go when one of three things happens, and only then:
- the bus moves off,
- the driver signals you on, or
- the red lights stop flashing.
Two exceptions, and they are narrow: the bus is on a different roadway, or you are on a controlled-access highway where the bus is in a loading zone pedestrians cannot cross. A painted centre line is not an exception, and neither is lane count.
Phones
A driver under 18 licensed on or after 1 September 2009 may not use any wireless communication device — hands-free included — until they turn 18. The only exception is an emergency.
Top speed limits
The Transportation Commission may set 75 mph on parts of the state highway system, 80 mph on stretches of IH-10 and IH-20 in named west Texas counties, and up to 85 mph where a highway is specifically designed for it. None of these apply by default — the posted sign governs.