HEAVY TRUCK BRAKES MICHIGAN MECHANIC
2026 QUESTIONS AND ANSWERS RATED A+
✔✔which one of these should be done most frequently? - ✔✔a. adjust the spiders.
b. lubricate the "s" cam.
c. check the brake chambers for moisture. (not correct awnser)
d. check the brake chamber push rod travel. (possible correct awnser)
✔✔air brake lines are msot often made of: - ✔✔a. brass and aluminum.
b. steeland nylon.
c. nylon and brass.
d. copper and nylon. (correct awnser)
✔✔to find leaks in airline fittings and service chambers, you should use: - ✔✔a. a halide
leak detector.
b. a vacuum gauge. (not correct awnser)
c. a brake pressure bleeder.
d. a soap suds mixture. (possible correct awnser)
✔✔a likely cause of grabbing brakes on a drive axle would be: - ✔✔a. a bad quick
release valve. (not correct awnser)
b. brakes adjusted too tight. (possible correct awnser)
c. grease or gear lube on linings.
d. weak shoe return springs.
✔✔the hydraulic service brakes will not release fully. what should you do first? - ✔✔a.
check the master cylinder for defects. (correct awnser)
b. check for a defective quick release valve.
c. run an engine vacuum test.
d. check the brake drums.
✔✔in the system shown below, air leaks from the relay valve exhaust port all the time.
the likely cause of this problem is: - ✔✔a. a leaky seal in the part at point d.
, b. a leaky seal in the part at point c. (correct awnser)
c. a leaky seal in the part at point e.
d. a lekay seal in the part at point a.
✔✔in the drawing below, the diaphragm at point e has failed. what must you do before
moving the truck? - ✔✔a. compress the spring at point d. (not correct awnser)
b. apply air pressure to point f.
c. compress the spring at point f.
d. release air pressure at area b.
✔✔in the drawing below: - ✔✔a. the parking brakes are applied and the service brakes
are released.
b. both parking and service brakes are released.
c. the service brakes are applied and the parking brakes are released.
d. both parking and service brakes are applied. (not correct awnser)
✔✔the trailer brakes do not release properly. the air pressureis normal and the
emergency service lines are hooked up properly. the problem could be caused by: -
✔✔a. dry or binding cam bushings.
b. a bad relay emergency valve.
c. a foot valve not returning to a fully released position.
d. all of the above. (correct awnser)
✔✔what should you do first before replacing the diaphragm on a spring brake type
emergency brake chamber? - ✔✔a. compress the spring brake. (possible correct
awnser)
b. back off the slack adjsuter.
c. disconnect the push rod clevis.
d. compress the diaphragm return spring. (not correct awnser)
✔✔cam actuated brake shoes are found to be making only partial contact with the
drum. to correct this condition, adjustment should be made to the: - ✔✔a. actuator
cable.
b. applying wedge.
c. eccentric anchor pins. (correct awnser)
d. roller follower.
✔✔water should be drained from air reservoirs: - ✔✔a. before adjusting slack adjusters.
b. daily or more frequently in cold or moist weather. (correct awnser)
c. before any attempt is made to replace a service chamber diaphragm.
d. to expel excess oil passed by the air pump.
✔✔a mechanic finds that the vacuum hose hooks up to the power booster has
collapsed. what should the mechanic do? - ✔✔a. replace the hose. (possible correct
awnser)
2026 QUESTIONS AND ANSWERS RATED A+
✔✔which one of these should be done most frequently? - ✔✔a. adjust the spiders.
b. lubricate the "s" cam.
c. check the brake chambers for moisture. (not correct awnser)
d. check the brake chamber push rod travel. (possible correct awnser)
✔✔air brake lines are msot often made of: - ✔✔a. brass and aluminum.
b. steeland nylon.
c. nylon and brass.
d. copper and nylon. (correct awnser)
✔✔to find leaks in airline fittings and service chambers, you should use: - ✔✔a. a halide
leak detector.
b. a vacuum gauge. (not correct awnser)
c. a brake pressure bleeder.
d. a soap suds mixture. (possible correct awnser)
✔✔a likely cause of grabbing brakes on a drive axle would be: - ✔✔a. a bad quick
release valve. (not correct awnser)
b. brakes adjusted too tight. (possible correct awnser)
c. grease or gear lube on linings.
d. weak shoe return springs.
✔✔the hydraulic service brakes will not release fully. what should you do first? - ✔✔a.
check the master cylinder for defects. (correct awnser)
b. check for a defective quick release valve.
c. run an engine vacuum test.
d. check the brake drums.
✔✔in the system shown below, air leaks from the relay valve exhaust port all the time.
the likely cause of this problem is: - ✔✔a. a leaky seal in the part at point d.
, b. a leaky seal in the part at point c. (correct awnser)
c. a leaky seal in the part at point e.
d. a lekay seal in the part at point a.
✔✔in the drawing below, the diaphragm at point e has failed. what must you do before
moving the truck? - ✔✔a. compress the spring at point d. (not correct awnser)
b. apply air pressure to point f.
c. compress the spring at point f.
d. release air pressure at area b.
✔✔in the drawing below: - ✔✔a. the parking brakes are applied and the service brakes
are released.
b. both parking and service brakes are released.
c. the service brakes are applied and the parking brakes are released.
d. both parking and service brakes are applied. (not correct awnser)
✔✔the trailer brakes do not release properly. the air pressureis normal and the
emergency service lines are hooked up properly. the problem could be caused by: -
✔✔a. dry or binding cam bushings.
b. a bad relay emergency valve.
c. a foot valve not returning to a fully released position.
d. all of the above. (correct awnser)
✔✔what should you do first before replacing the diaphragm on a spring brake type
emergency brake chamber? - ✔✔a. compress the spring brake. (possible correct
awnser)
b. back off the slack adjsuter.
c. disconnect the push rod clevis.
d. compress the diaphragm return spring. (not correct awnser)
✔✔cam actuated brake shoes are found to be making only partial contact with the
drum. to correct this condition, adjustment should be made to the: - ✔✔a. actuator
cable.
b. applying wedge.
c. eccentric anchor pins. (correct awnser)
d. roller follower.
✔✔water should be drained from air reservoirs: - ✔✔a. before adjusting slack adjusters.
b. daily or more frequently in cold or moist weather. (correct awnser)
c. before any attempt is made to replace a service chamber diaphragm.
d. to expel excess oil passed by the air pump.
✔✔a mechanic finds that the vacuum hose hooks up to the power booster has
collapsed. what should the mechanic do? - ✔✔a. replace the hose. (possible correct
awnser)
