CDL Mile

CDL disqualifications: what costs you your license

Section 1.3 of the CDL handbook lists the offenses that disqualify a commercial driver and for how long. It is tested on the General Knowledge test.

Key facts

Part ofthe General Knowledge test (80% to pass)
Handbook section§1.3 CDL disqualifications
Questions in CDL Mile's bank9

Key rules

  • § 1.3.5p. 1-8

    Every driver must have enough room to drive all the way through a crossing without stopping. Failing to do so is a crossing violation, and a first violation costs your CDL for at least 60 days.

    Railroad-highway Grade Crossing Violations

  • § 1.3.3p. 1-8

    The handbook defines excessive speeding as 15 mph or more over the posted limit. It is one of the serious traffic violations that can lead to losing your CDL.

    Serious Traffic Violations

  • § 1.3.3p. 1-8

    Following too closely, erratic lane changes and reckless driving are all serious traffic violations. Three or more of them in a CMV within three years costs your CDL for at least 120 days.

    Serious Traffic Violations

Try two questions

General Knowledge · CDL disqualifications

On a first offense, what is the minimum time you lose your CDL for leaving the scene of an accident while driving a CMV placarded for hazardous materials?

Tap an answer to see the explanation and the handbook page.

General Knowledge · CDL disqualifications

A driver who already lost a CDL once for driving a CMV under the influence of alcohol is convicted of the same offense a second time. What penalty does the handbook set?

Tap an answer to see the explanation and the handbook page.

More General Knowledge topics

Medical documentationOther CDL rulesVehicle inspectionBasic vehicle controlShifting gearsSeeingCommunicatingControlling speedManaging spaceSeeing hazardsDistracted drivingAggressive drivers and road rageDriving at nightDriving in fogDriving in winterDriving in very hot weatherRailroad-highway crossingsMountain drivingDriving emergenciesAntilock braking systemsSkid control and recoveryCrash proceduresFiresAlcohol, drugs and illnessHazardous materials rules for all driversInspecting cargoWeight and balanceSecuring cargoCargo needing special attentionAll General Knowledge →

Sources

Texas Commercial Motor Vehicle Drivers Handbook (DL-7C), revised March 2026, Texas Department of Public Safety. Page references are to its printed page numbers. CDL Mile is independent and not affiliated with Texas DPS.

Updated for the March 2026 Texas CDL handbook (DL-7C). Last checked November 4, 2026.

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