AK CDL General Knowledge common mistakes
AK CDL General Knowledge · Understand the traps and how to avoid them.
Walks the pre-trip checklist in whatever order, skipping the static air-leak test and the applied-leak test, and never states the pass/fail numbers.
The checklist gets studied as a list of parts to look at rather than a sequence of tests with limits, so the candidate has never rehearsed the sequence out loud or done it hands-on.
What to do instead
Rehearse the sequence until automatic and say each threshold aloud: build to governor cut-out, static leak (no more than 3 psi/min on a single vehicle, 4 psi/min on a combination), applied leak with the pedal held (3 psi/min), warning by 60 psi, spring brakes applying between 20 and 45 psi, and a build rate that recovers in the required time.
Backing a tractor-trailer, turns the wheel the same way the cab should move, then saws the wheel back and forth until the rig jackknifes.
It is a car reflex: in a car you point the front where you want to go. With a trailer the pivot point is behind the driver, so the trailer's response is reversed and delayed.
What to do instead
Use the 'turn toward the problem' rule: to move the trailer's rear to the left, turn the wheel left while backing. Make one small input, wait for the trailer to respond, then correct. When it goes wrong, stop, pull forward, or get out and look rather than overcorrecting.
Changes lanes using the mirrors only, never turning the head to clear the area alongside the cab and directly behind the trailer.
Mirrors in a long conventional cab leave large blind areas, but a car habit trains the driver to treat the mirror image as complete.
What to do instead
Set mirrors before the trip, then use the full sequence every time: signal early, check both mirrors, and turn the head to look into the blind spot on the side you are moving toward. Remember the right-side No-Zone is larger than the left.
Holds a flat three-second following gap at highway speed in a long combination, on ice or dry pavement.
The three-second car rule is overlearned and crowds out the commercial rule of one second per 10 feet of vehicle length, plus the extra second above 40 mph.
What to do instead
Compute the gap from vehicle length: one second per 10 feet below 40 mph, add one second above 40 mph, and add more for snow, ice, rain, or poor visibility. A 70-foot rig at 55 mph needs at least eight seconds on dry pavement, and far more on ice.
When a vehicle cuts in, brakes hard and yanks the wheel at the same time, locking the steering axle and losing control.
Panic habits come straight from driving a car, and the candidate never learned when stopping in a straight line beats trying to steer around the hazard.
What to do instead
Brake in a straight line first, using controlled braking (heel on the floor, firm steady pressure) or stab braking if the vehicle has drum brakes, and release to steer only after speed is down. If the wheels lock, release the brake and reapply.
In a rear-wheel skid, steers away from the slide and holds that input, turning a small skid into a full spin.
The phrase 'steer into the skid' gets memorized and then inverted under stress, and the driver keeps braking, which keeps the wheels sliding.
What to do instead
Get off the brake and throttle, steer in the direction the rear is sliding (trailer coming left means steer left), and counter-steer promptly as traction returns. Turn off the engine brake and cruise control on ice, and practice on a closed lot.
Keeps driving when the low-air warning sounds, planning to stop at the next exit or shop.
The 60-psi warning number is memorized but not what it means: spring brakes will apply automatically in the 20-to-45-psi range and stop the vehicle wherever it is.
What to do instead
Treat the buzzer as a stop-now instruction: pull off safely before pressure reaches the spring-brake range. Know the leak rates, the build rate, and that the parking brake knob will pop out on its own when pressure drops far enough.
Counts straps and decides the load is legal because there are 'enough of them,' without adding up working load limits against the weight of the cargo.
The aggregate 50-percent rule and the one-tie-down-per-10-feet rule are two different numbers, and candidates memorize counts instead of the calculation.
What to do instead
Add the marked working load limit of every tiedown and confirm the total is at least half the cargo weight. Use at least one tiedown per 10 feet of cargo (two for articles longer than 5 feet but under 10 feet), keep proper angles, and protect the straps from sharp edges.
Plans a run assuming an off-duty break resets the 14-hour on-duty window, and treats the 30-minute break as extending the 11-hour driving limit.
Three separate clocks (11 hours driving, 14 hours on duty, a 30-minute break after 8 cumulative driving hours) get learned as one vague 'hours' number.
What to do instead
Draw the clocks side by side and track them daily: only 10 consecutive hours off resets both the 11 and the 14; the 30-minute non-driving break after 8 cumulative driving hours does not extend either limit; fueling, loading, and waiting all count against the 14.
On an Alaska gravel highway, keeps paved-road speeds and following gaps, then loses the road in dust or hits washboard and frost heaves at speed.
Preparation focuses on paved-road stopping distances and city No-Zone diagrams, so the Alaska material on gravel, dust, frost heaves, and moose is skimmed.
What to do instead
Slow to a speed that lets you stop within the distance you can actually see, run headlights, hang back until the dust settles, brake before a rough section rather than in it, and scan far ahead for moose and heaved pavement.