Kentucky CDL Practice Test

Correct answer: Six months — and it must be held at least 14 days before a skills test

Kentucky issues the CDL instruction permit valid for six (6) months. You must hold the permit at least 14 days before the skills test can be administered.

Correct answer: One time — if you do not pass the road skills test before the renewal expires, you must reapply

A Kentucky CDL permit may be renewed only once. If you do not pass the road skills test before the renewed permit expires, you must reapply and pay all fees and pass all written tests again.

Correct answer: 50 questions — with 25 more on Air Brakes and 20 more on Combination Vehicles when those apply

Kentucky’s General Knowledge test has 50 questions. A Class A applicant answers 20 more on Combination Vehicles, and anyone driving a vehicle with air brakes answers 25 more on Air Brakes.

Correct answer: Written or oral form — but there is no oral test for the Hazardous Materials endorsement

Kentucky administers the CDL knowledge test in either written or oral form. The one exception is the Hazardous Materials endorsement, which has no oral test.

Correct answer: $11 — or $14 for a REAL ID permit

Kentucky charges $11 for a CDL instruction permit, or $14 for a REAL ID permit. Total CDL costs vary with class, endorsements, number of test attempts, and whether you choose a REAL ID.

Correct answer: You must wait 24 hours before retesting, but the General Knowledge test may be retaken indefinitely with no retest fee

You must correctly answer 80% of each test to pass. After a failed General Knowledge test you must wait 24 hours before retesting, but it may be retaken indefinitely with no retest fee. The combination, air brake, and endorsement tests carry a $5 retest fee after the first failure.

Correct answer: Drive only in Kentucky intrastate commerce and do not drive a school bus or haul hazardous materials

A CDL may be issued to an individual 18 to 20 years old who holds a valid Class D license and passed the vision and knowledge tests, provided they drive only in Kentucky intrastate commerce and do not drive a school bus or haul hazardous material. The license carries a "K" (Intrastate Only) restriction.

Correct answer: In their home state of license issuance; skills-test scores from outside Kentucky are not accepted

Individuals 18 to 20 must complete CDL skills testing in their home state of license issuance. Kentucky does not accept skills-test scores for applicants under 21 who test outside Kentucky, and this also applies to any driver with a "K" restriction regardless of age.

Correct answer: Intrastate Only — the driver may not operate a CMV in interstate commerce

The "K" restriction limits the driver to Kentucky intrastate commerce. Other Kentucky restriction codes include "L"/"Z" (air brakes), "E" (no manual transmission), "O" (no tractor-trailer), and "V" (medical variance).

Correct answer: Receive a license restriction limiting them to a CMV without an air brake system

Failure to show basic knowledge of an air brake system results in a restriction limiting the driver to a vehicle without air brakes. To remove an "L" or "Z" restriction you must obtain a permit, wait 14 days, and pass a complete CDL skills test in an air-brake-equipped vehicle.

Correct answer: You may have difficulty getting the vehicle into the next gear

If you stay in neutral too long, it can be hard to get the vehicle into the next gear. Don’t force it — return to neutral, release the clutch, match engine speed to road speed, and try again.

Correct answer: Return to neutral, release the clutch, increase engine speed to match road speed, and try again

Don’t force the shift. Return to neutral, release the clutch, bring engine speed up to match road speed, and try again — forcing it can damage the transmission.

Correct answer: Engine sounds

With either the rpm or road-speed method, you can also learn to use engine sounds to judge when to shift, though the gauges remain the reliable reference.

Correct answer: A low gear — usually lower than the gear needed to climb the same hill

Downshift before starting down a hill to a speed you can control without using the brakes hard — usually a lower gear than you would use to climb the same hill. Otherwise the brakes can overheat and fade.

Correct answer: It lets you use some power through the curve for stability and speed up as you exit

Slow down and downshift to the right gear before entering a curve. This lets you apply some power through the curve to keep the vehicle stable, and speed up as soon as you are out of it.

Correct answer: Riding the brakes can overheat them and cause them to lose braking power

If you rely on the brakes down a long grade they can overheat and lose their braking power. Downshifting lets engine braking help control your speed and saves the brakes.

Correct answer: Select a low range so the transmission does not shift up beyond that gear

Select a low range to get greater engine braking going down grades; the lower ranges keep the transmission from shifting up beyond the chosen gear (unless governor rpm is exceeded). Using this braking effect is very important on grades.

Correct answer: They help slow the vehicle and reduce brake wear

Retarders help slow the vehicle, reducing how much you need the brakes and cutting brake wear. The four basic types are exhaust, engine, hydraulic, and electric retarders.

Correct answer: On poor traction, the retarder can cause the drive wheels to skid

When the drive wheels have poor traction, applying the retarder may cause them to skid. Therefore you should turn the retarder off when the road is wet, icy, or snowy.

Correct answer: Steer around the obstacle — you can usually turn to miss it faster than you can stop

Stopping is not always the safest thing to do. When you do not have room to stop, you can almost always turn to miss an obstacle more quickly than you can stop. (Top-heavy vehicles and multi-trailer rigs, however, may flip if turned sharply.)