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3 10T 20 25 EXAM QUESTIONS AND CORRECT ANSWERS
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when reinforcing a frame, how is the reinforcement material is attached 1.By cutting material ends at 45 degrees and bolting to web
- By cutting material ends at 90 degrees and bolting to flange
- By cutting material ends at 45 degrees and bolting to flange
- By cutting material ends at 90 degrees and bolting to web - ANSWER By cutting material ends at 45 degrees and bolting to web
During operation play is noticed between the trailer and fifth wheel, what is the cause
- Lock jaws out of adjustment
- Leaking slide lock cylinder
- Worn upper coupler
- Worn pivot bushings - ANSWER Lock jaws out of adjustment
What is done to repair a broken spring pack
- Replace both shock observers and replace broken spring pack
- Replace one spring pack and shock observer
- Replace all broken spring packs on all axles
- Replace both spring packs on the same axle - ANSWER Replace both spring packs on the same axle
What is the next step to adjust the air suspension ride height after blocking the wheels
- Release the air brakes
- Set to loaded ride height
- Adjust at the ride height
- Dump air bags - ANSWER Release the air brakes
A truck has a drive line vibration, what is the cause
- Broken shock absorber
- Out of phase drive shaft
- Worn transverse torque rod bushings
- Broken cross member - ANSWER Out of phase drive shaft
On a bottom dump trailer, an air bag is torn from the pedestal, what is the cause
- Bent shock
- Broken shock
- A levelling valve is adjusted too low
- A worn out beam bushing - ANSWER Broken shock
What is the procedure to determine a set of tandem axles are parallel to each other
- Block the wheels, release the brakes, check the ride height then compare the axle center line on each side using a trammel bar
- Block the wheels, release the brakes, check the ride height then use a measuring tape to measure the narrowest point between the tires on each side
- Block the wheels, release the brakes, check the ride height measure between the inside of wheel and frame then compare that measurement with the opposite side
- Block the wheels, release the brakes, verify the inclination angle on one side then compare it to the other side - ANSWER Block the wheels, release the brakes, check the ride height then compare the axle center line on each side using a trammel bar
Which tool is used to measure a trailer king pin wear
- Tape measure
- Straight edge
- Inside caliper
An oil leak is found at the hub seal, what is the cause
- Loose wheel bearing
- Under inflated tire
- Tires are mismatched
- Over sizes brake drums - ANSWER Loose wheel bearing
During inspection, a drive axle flange gasket is leaking, what is the cause
- Loose axle studs
- Loose wheel bearing
- Incorrect bearing end play
- Incorrect axle own size - ANSWER Loose axle studs
The wheel rim has turned on a spoke hub, what is done
- Remove wheel nuts, inspect clamps then re-torque all wheel nuts
- Disassemble, inspect replaced wheel nuts and clamps as required then reassemble wheel
- Disassemble, inspect replaced components as required, reassemble wheel then check run out
- Remove and replace wheel nut, re-torque all wheel nuts then check run out - ANSWER Disassemble, inspect replaced components as required, reassemble wheel then check run out
What is the procedure to install a steel and aluminum wheel combination
- Install teflon spacer between steel wheel and drum then torque
- Install steel wheel, install aluminum wheel then torque
- Install aluminum wheel, install steel wheel then torque
- Install teflon spacer between wheel then torque - ANSWER Install teflon spacer between wheel then torque
CAB
What is used to lubricate seat sliders
- Engine oil
- Penetrating oil
- Chasis grease
- White lithium grease - ANSWER White lithium grease
During operation, a power window stops halfway up. What is the cause
- Strict gears in the window regulator
- Strict gears in the window driver motor
- Too much friction in the window tract
- Open ground circuit on the window motor - ANSWER Too much friction in the window tract
Cruise control is not functioning, which components are checked
- Clutch switch, brake switch, neutral safety switch and cruise control switch
- Clutch switch, brake switch and cruise control switch
- Door switch, brake switch, and cruise control switch
- Door switch, brake switch, neutral safety switch, and cruise control switch - ANSWER Clutch switch, brake switch and cruise control switch
A vehicle information door tag is damaged, what is done
- Contact OEM for replacement data and store in cab
- Record the data on the glove box door
- Contact OEM for replacement then reinstall on door frame
- Record the data on the door frame - ANSWER Contact OEM for replacement then reinstall on door frame
What is done when installing a replacement SRS ECU
- Clean contact pins to prevent damage to the ECU from corrosion
- Avoid touching pins to prevent damage to the ECU from static discharge
- Apply die-electric compound to ensure connection to the ECU
- Connect batteries and cycle key to recharge SRS capaclitor energy - ANSWER Avoid touching pins to prevent damage to the ECU from static discharge
Refer to figure 50: The spliced joint had a 10 Volt drop, what is the result
- Relay will not power on
- Relay will not switch
- Dome light is bright
- Dome light is dim - ANSWER Dome light is dim
What is the cause of a swollen wire
- High amperage draw
- Brake in the insulation
- High resistance in the wire
- Incorrect routing of the wire - ANSWER High amperage draw
When checking a 3 wire sensor, the operating range is high, what is the cause
- The sensor internally shorted to ground
- The sensor signal wire is shorted to ground
- Signal wire shorted to positive voltage
- Sensor circuit is open - ANSWER Signal wire shorted to positive voltage
What is the procedure to replace a sensor connector
- Remove the pins from the wires, remove wires from the body, remove seal from the wires, install new seals, install new pins, then install into new body
- Remove the pins from the wires, remove wires from the body, remove seal from the wires, install new pins, install new seals, then install into new body
- Remove wire from the body, remove pins from the wire, remove seals from the wire, install new seals, install new pins, then install into new body
- Remove the wires from the body, remove pins from the wire, remove seals from the wire, install new pins, install new seals, then install into new body - ANSWER Remove wire from the body, remove pins from the wire, remove seals from the wire, install new seals, install new pins, then install into new body
What are the steps to replace data link wires
- Twist the wires 2 times per inch and select the wire gauge as per manufacture specification
- Twist the wires 2.5 rimes per inch and select the wire gauge as per manufacture specification
- Twist the wires 3 times per inch and select the wire gauge as per manufacture specification
- Twist the wires 3.5 times per inch and select the wire gauge as per manufacture specification - ANSWER Twist the wires 3 times per inch and select the wire gauge as per manufacture specification
DRIVE TRAIN A clutch release bearing is over greased, what is the result
- Release bearing is noisy
- Clutch disc is contaminated resulting in mis-adjustment
- Clutch disc is contaminated resulting in slippage
- Hard shifting - ANSWER Clutch disc is contaminated resulting in slippage
A new clutch has been installed but will not disengage, what is the cause
- Fly wheel was not machined
- Clutch brake was not replaced
- Disc is installed backwards
- Shift counter shaft
- Check output shaft end play - ANSWER Install output shaft yoke
What is the procedure to adjust shift link gauge
- Put the cabs selector in drive, disconnect the shift cable at the transmission, move the transmission lever to neutral then adjust the cable
- Put the cabs selector in reverse, disconnect the shift cable at the transmission, move the transmission lever to reverse then adjust the cable
- Put the cabs selector in reverse, disconnect the shift cable at the transmission, move the transmission lever to neutral then adjust the cable
- Put the cabs selector in neutral, disconnect the shift cable at the transmission, move the transmission lever to neutral then adjust the cable - ANSWER Put the cabs selector in neutral, disconnect the shift cable at the transmission, move the transmission lever to neutral then adjust the cable
A speedometer malfunction during the operation of a vehicle, what is the cause
- Engine crank shaft sensor has failed
- Engine cam shaft sensor has failed
- Transmission input speed sensor has failed
- Transmission output speed sensor has failed - ANSWER Transmission output speed sensor has failed
During disc assembly of an automated transmission, which components are inspected for wear
- Clutch disk, plantary gear sets and shifts solenoid
- Clutch disk, plantary gear sets, and transmission case
- Clutch disk, shifts solenoid, and transmission case
- Clutch disk, shifts solenoid and valve body - ANSWER Clutch disk, shifts solenoid, and transmission case
What is the procedure to check for fault codes on an automated transmission
- Connect service tool, open OEM software, scan for active faults, diagnose as necessary then clear fault once repaired
- Connect service tool, open OEM software, scan for inactive faults, diagnose as necessary then clear fault once repaired
- Connect service tool, open OEM software, scan for active and inactive faults, diagnose as necessary then clear fault once repaired
- Connect service tool, open OEM software, scan for active and inactive faults, then clear faults - ANSWER Connect service tool, open OEM software, scan for active faults, diagnose as necessary then clear fault once repaired
The shift selector display of an automated transmission is flashing N, what is the result
- Engine will not start
- Engine will not turn off
- Transmission will not shift
- Transmission will not shift into R - ANSWER Transmission will not shift
The auxiliary section of an automated transmission shifts slowly, what is the cause
- Low air pressure to clutch actuator
- Low air pressure from air regulator
- Short in speed sensor
- Wear on synchronizer ring - ANSWER Low air pressure from air regulator
There is a leak at the output shaft area of a truck, with an automated transmission, what is done after removing the output shaft yoke
- Remove u-joint, remove seal, then install new shaft seal
- Remove drive shaft, remove seal, then install new shaft seal
- Inspect seal bore, remove seal, then install new shaft seal
- Remove seal, inspect seal bore, then install new shaft seal - ANSWER Remove seal, inspect seal bore, then install new shaft seal
- An open in the retarder harness
- An unplugged retarder harness
- Reversed wiring in the retarder harness - ANSWER A short in the retarder harness
STEERING CHASES, FRAMES, SUSPENSIONS, WHEELS, HUBS, AND TIRES What is the procedure to measure radial king pin play
- Raise the vehicle, install dial indicator magnetic base on the i-bean then measure vertical movement between knuckle and axle
- Raise the vehicle, install dial indicator magnetic base on the i-bean then measure horizontal movement between knuckle and axle
- Raise the vehicle, install dial indicator magnetic base on the knuckle then measure horizontal movement between the wheel and knuckle
- Raise the vehicle, install dial indicator magnetic base on the knuckle then measure vertical movement between the wheel and knuckle - ANSWER Raise the vehicle, install dial indicator magnetic base on the i-bean then measure vertical movement between knuckle and axle
While driving straight forward, the vehicle steering wheel is in an off-centered condition, what is the cause
- Cab air suspension is deflated
- Bent steering shaft
- Bent drag link
- Worn right hand tie rod end - ANSWER Worn right hand tie rod end
A steering wheel is binding during operation no rough roads, what is the cause
- Incorrect sector gear backlash
- Seized steering shaft U joint
- Worn power steering pump
- Seized slip joint on a steering shaft - ANSWER Seized slip joint on a steering shaft
What is the first adjustment made during a front end alignment
- Caster
- King pin inclination
- Camber
- Toe - ANSWER Toe
What is inspected before performing a front-end alignment
- Tire thread depths, wheel bearing, suspension components and steering linkage
- Tire pressure, wheel bearing and suspension components
- Tire pressure, wheel bearing, power steering components linkage
- Tired pressure, wheel bearing, suspension components and steering linkage - ANSWER Tire thread depths, wheel bearing, suspension components and steering linkage
What is the cause of rust streaks on a frame rail
- Constant overloading
- Flawed paint job
- Over torque cross member fastener
- Loose cross member fastener - ANSWER Loose cross member fastener
When reinforcing a frame, how is the reinforcement material is attached
- By cutting material ends at 45 degree and bolting to web
- By cutting material ends at 90 degree and bolting to flange
- By cutting material ends at 45 degree and bolting to flange
- By cutting material ends at 90 degree and bolting to web - ANSWER By cutting material ends at 45 degree and bolting to web
Refer to figure 36: batteries are not fully charging, which location is the problem at
disconnect switch, connect volt meter to both ends of the starter ground cable then crank engine while measuring voltage
What is done when installing a replacement SRS ECU
- Clean contact pins to prevent damage to the ECU from corrosion
- Avoid touching pins to prevent damage to the ECU from static discharge
- Apply die-electric compound to ensure connection to the ECU
- Connect batteries and cycle key to recharge SRS capacitor energy - ANSWER Avoid touching pins to prevent damage to the ECU from static discharge
A truck air brakes operate normally when a trailer is connected the brakes are weak, what is the cause
- A faulty quick release valve
- Faulty tractor protection valve
- Faulty treadle valve
- Faulty pressure protection valve - ANSWER Faulty tractor protection valve
During a chuff test, one chuff is not audible and no active ABS code is present, what is the cause
- Open modulator harness
- Open ABS sensor harness
- Defective ABS sensor harness
- Defective modulator - ANSWER Defective modulator
What is checked after installing a new rotor
- Thickness variation
- Wheel torque
- Bearing preload
- Lateral run out - ANSWER Lateral run out
Refer to figure 36: batteries are not fully charging, which location is the problem at
- V
- V
- V
- V4 - ANSWER V
Refer to figure 53 given the following information: There is no communication with J Voltage between A & C = 2.38 Volts Voltage between A & B = 12.7 Volts Voltage between A & D = 2.38 Volts
What is the cause
- CAN low short to power
- CAN high short to power
- Terminating resistor open
- Terminating resistor shortened - ANSWER CAN high short to power
What is done when installing a replacement SRS ECU
- Clean contact pins to prevent damage to the ECU from corrosion
- Avoid touching pins to prevent damage to the ECU from static discharge
- Apply die-electric compound to ensure connection to the ECU
- Connect batteries and cycle key to recharge SRS capacitor energy - ANSWER Avoid touching pins to prevent damage to the ECU from static discharge
The pressure in a blended HVAC system is sufficient but the vent temperatures are higher than specification. What is the cause
A heating and refrigeration unit has failed in the pre-trip mode and the engine has shut down. What is the cause
- Broken exhaust clamp on the manifold
- Leaking fuel tank at the mounting straps
- Active code in the ECM
- Loose connection between ECM and display - ANSWER Active code in the ECM
What is done to increase system air pressure
- Adjust governor by turning screw counter clockwise then verify pressure with master gauge
- Adjust governor by turning screw clockwise then verify pressure with master gauge
- Install higher CFM compressor then verify pressure with master gauge
- Install higher setting release valve then verify pressure with master gauge - ANSWER Adjust governor by turning screw counter clockwise then verify pressure with master gauge
When performing a tune up on a coil on plug gasoline engine, which components are replaced
- Spark plug, fuel filter and air filter
- Spark plug wires, spark plug, air filter and fuel filter
- Sparks plug, ignition coiled and fuel filter
- Spark plug air filters, fuel filter and oxygen sensor - ANSWER Spark plug, fuel filter and air filter
A unit will not crank when testing, the positive terminal at the starter has 12 Volts and 8 Volts to the S terminal, what is tested next
- Neutral safety switch
- Voltage drop on the positive battery cable
- Voltage drop on the negative battery cable
- Starter relay - ANSWER Starter relay
A starter circuit engages there is 12 Volts delivered to the starter remoter and 0 volts at the ground cable, the engine does not crank, what is the cause
- Brushes are not contacting the armature
- A short circuit within the motor
- Faulty starter motor soleniod
- Faulty neutral safety switch - ANSWER Faulty starter motor soleniod
Refer to figure 47, The 15A fuse is blown, what is the cause
- No ground at the AC clutch coil relay
- High resistance across the binary switch
- High resistance at the AC clutch coil relay
- The AC and electromagnetic coil is shortened - ANSWER The AC and electromagnetic coil is shortened
Refer to figure 57, the master lightning switch is turn to clearance/marker position, and the left head light also comes on, what is the problem
- Short to ground at pin 87A of the truck clearance/marker light relay
- Short to ground at pin 86 of the truck clearance/marker light relay
- Short to power at pin 87A of the truck clearance/marker light relay
- Short to power at pin 86 of the truck clearance/marker light relay - ANSWER Short to power at pin 86 of the truck clearance/marker light relay
Refer to figure 45: What is the torque sequence for the exhaust manifold
- A,C,E,H,J,B,D,F,G,I
- A,C,E,F,D,B,J,H,G,I
- A,B,C,J,D,I,F,G,E,H
- A,B,G,F,H,E,J,C,I,D - ANSWER A,B,C,J,D,I,F,G,E,H
