Illinois CDL Practice Test

Correct answer: 30 questions, with a minimum score of 80%

Illinois publishes its real test format: the general (core) knowledge exam consists of 30 standardized multiple-choice questions, and every CDL applicant must score at least 80% to pass.

Correct answer: A valid Illinois driver’s license with more than one year before it expires

Illinois requires CLP/CDL applicants to have a valid Illinois driver’s license that has more than one year remaining before it expires, before testing begins.

Correct answer: $50

The Illinois CLP fee is $50 for all non-CDL license holders, and the same $50 applies to re-issue an initial CLP.

Correct answer: Retaking all applicable written tests (and redoing any completed skills tests) and paying the full CLP fee

An original CLP expires one year from the date of initial issuance. On re-issuance, all applicable written exams must be retaken, any completed skills/drive testing must be redone, and the full CLP fee is charged again.

Correct answer: At least 14 calendar days from the CLP issue date

All Illinois CLP holders — initial, renewal, or upgrading — must hold the CLP for a minimum of 14 calendar days from the issue date before conducting skills and drive testing.

Correct answer: One year

Written knowledge test results are valid for a maximum of one year in Illinois (and can be valid for less, depending on the circumstances). If you don’t finish the process in time, you retest.

Correct answer: 18 years old — but driving is limited to within Illinois until age 21

Illinois issues a CLP/CDL at age 18, which also allows transporting hazardous materials intrastate (within Illinois only). You must be at least 21 to drive a CMV in interstate commerce.

Correct answer: Drive a CMV in interstate commerce or transport passengers

Illinois requires commercial drivers to be at least 21 to drive a CMV involved in interstate commerce or to transport passengers. At 18 you may hold a CLP/CDL for driving within Illinois.

Correct answer: C — Charter Bus

The Charter Bus (C) endorsement is Illinois-only. It is required to operate a charter-type bus transporting school children grades 12 and under on behalf of an Illinois school district. P, N, S, H, X, and T are the standard national endorsements.

Correct answer: CDL intrastate only — you may not drive a CMV outside Illinois

The K restriction limits the CDL to intrastate driving only. (L is the no-air-brakes restriction and B is corrective lenses.)

Correct answer: Engine speed (rpm) and road speed (mph)

You can shift up by watching engine speed (rpm) on the tachometer, or by learning the road speed (mph) each gear is good for and using the speedometer. Many drivers also learn engine sounds.

Correct answer: The rpm at which you shift becomes higher as you move up through the gears

Some newer vehicles use progressive shifting: the shift-point rpm becomes higher as you move up in the gears. Find out what is right for the vehicle you operate.

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.