How do you test service brakes? Wait for normal air pressureRelease parking brakeMove

CA DMV Commercial Handbook Flashcards How do you test service brakes?Wait for normal air pressureRelease parking brakeMove vehicle forward slowly (approx 5 mph)Apply brakes firmly using pedalNote any "pulling" to on side, unusual feel, or delayed stopping action.What are the 4 basic types of retarders? ExhaustEngineHydraulicElectric What is the minimum tread depth for tires? 4/32 for front tires2/32 for all other tires How much space should you keep in front of you? 1 second for each 10 feet of vehicle length (below 40 mph)add 1 second for safety above 40 mph When do automatic slack adjusters adjust themselves?During full brake applications When is a full stop required at a railroad crossing?Nature of the cargo (hazardous materials, passenger vehicle, etc.)Otherwise required by law Hydroplaning is more likely if?Tire pressure is low or tread is worn If the vehicle is hydroplaning, do not use what? Your brakes When should you turn the retarder off?Whenever the road is wet, icy, or snow covered What is the rule on passing or overtaking a vehicle?You must be traveling at least 10 mph faster and complete the pass within 1/4 mile What is the total stopping distance equation for a vehicle with air brakes?Perception distance + Reaction distance + Brake lag distance + Braking distance When you double your speed from 20 mph to 40 mph, the impact or striking power of your vehicle is how much greater?

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If you must stop open a road or the shoulder of any road, you must put out your emergency warning devices within how long?10 minutes What is an Active railroad crossing?Has traffic control devices to regulate trafficDevices include red lights, bells, and/or gates How much play can you have in the steering wheel? no more than 10 degrees(approx 2 inches on a 20 inch wheel) What are the 4 ways a skid happens?Over-brakingOver-steeringOver-accelerationDriving too fast How do you check slack adjusters?Park on level ground, chock wheels, release parking brakes. Pull on each slack adjuster. Cannot move more that 1 inch How thin can brake linings be?Not less than 1/4" Brake drums or discs must not have cracks longer than what?1/2 the width of the friction area What are the 2 types of railroad crossings? Passive crossings and Active crossings What is the safety relief valve in the brake system?A valve that protects the brake system from over-pressurization. Usually set to open around 150 psi On a wet road, how much should you reduce your speed?By 1/3

How do you test the parking brake?Fasten seat beltSet parking brakeGently pull against it in a low gear to test parking brake will hold What is "brake lag?"The time required for the brakes to work after the brake pedal is pushed What is the parking brake system?Applies and releases parking brakes while in use What is a Passive railroad crossing?Does not have any type of traffic control deviceThe decision to stop or proceed rests entirely on your handsPassive crossings require you to recognize the crossing, search for any train, and decide if there is sufficient clear space to cross safely When will the spring brakes come on fully? Around 20-45 psi What are the 3 good rules for using turn signals? Signal earlySignal continuouslyCancel your signal If a vehicle with automatic slack adjusters are out of adjustment, what should you do?Take the vehicle to a repair facility ASAP to have problem corrected What is the Cut in level?Around 100 psi What should you do while driving in fog? Use low beam and fog lights even in daytimeTurn on your 4-way emergency flashers What is brake fade?Results from excessive heat causing chemical change to brake lining, which reduces friction, and cause expansion of brake drumsAs drums expand, brake shoes and linings have to move farther to contact the drums and the force is reduced How does ABS help you?Avoids wheel lock up and maintain controlShould be able to steer around an obstacle while brakingMay or may not be able to stop faster

• hours of sleep or less effects your risk how? Triples your risk

How should you respond during a tire failure? Hold steering wheel firmlyStay off the brakeCheck the tires What is the principal way of controlling your speed on downgrades?The braking effect of the engine What is the applied leakage test?Build air pressure to governor cut outShut of engineChock wheelsRelease parking brakeFully apply brake for 1 minCannot drop more than 3 psi What is the static leakage test?With a basically fully charge air system (within effective operating range for compressor), turn off engine, release all brakes, and let system settle.Time for 1 min (should not drop more than 2 psi) What is the service brake system?The brake system during normal driving What is the rate of air pressure build up test? Engine must be operating at idle (600-900 rpms)Observe air pressure build upShould be less than 45 seconds from 85psi-100psi What is the proper braking technique while going downhill?Apply brakes just hard enough to feel a definite slow downRelease brakes once your speed reaches 5 mph below "safe" speedContinue until you've reached the bottom of the hill

What are the major signs of tire failure? SoundVibrationFeel What is the equation for total stopping distance? Perception distance + reaction distance + braking distance What emergency equipment should vehicles have? Fire extinguisherSpare electrical fusesWarning devices for parked vehicles (3 triangles, 6 fusees, or 3 liquid burning flares) When should your low air pressure warning come on?Around 55-75 psiMust have a red light but may or may not have a buzzer All vehicles built since when have automatic slack adjusters?1994 When are leaf springs considered out of service? if 1/4 or more are broken or missing When you triple your speed from 20 mph to 60 mph, the impact or striking power of your vehicle is how much greater?

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What is a hazard?Any road condition or other road user that is a possible danger What is the cut out level?Around 125 psi (but by 140) Most good drivers look how far ahead?12 to 15 secondsLower speeds: 1 blockHigher speeds: 1/4 mile When driving in heavy traffic, what is the safest speed?The speed of other vehicles What is the emergency brake system?Uses parts of the service and parking brake systems to stop vehicle in a brake system failure How often should you inspect the tires when driving in hot weather?Every 2 hours or every 100 miles