310T Practice Exam #2
When lengthening a truck frame, at what angle should the frame be cut?! 30 degrees to the frame centreline 60 degrees to the frame centreline 90 degrees to the frame centreline 120 degrees to the frame centreline
60 degrees to the frame centreline
When assembling Deutsch connectors, how much insulation should be stripped away from each wire before crimping?! 2mm 6mm 10mm 15mm
6mm
What could cause slippage in only one gear range of an automatic transmission?! A defective governor A defective or leakage clutch apply piston seal Worn transmission oil pump gears Low transmission fluid level
A defective or leakage clutch apply piston seal
When performing a stall test on a truck equipped with an automatic transmission, what could cause a low rpm stall reading?! A failed clutch in the transmission A failed stator one-way clutch Worn turbine fins A low transmission fluid level
A failed stator one-way clutch
In a standard transmission, what could cause gear slipout?! Varnish buildup on the mainshaft Bindingsliding clutch gears A weak or broken detent spring A dragging clutch pilot bearing
A weak or broken detent spring
A new drive pinion with a "+1" pinion code variation number is being installed in a final drive. If the original pinion was stamped "-1", what would have to be done prior to pinion installation?! Add 0.001" (0.0254 mm) to the shim pack Remove 0.001" (0.0254 mm) from the shim pack Add 0.002" (0.0508 mm) to the shim pack Remove 0.002" (0.0508 mm) from the shim pack
Add 0.002" (0.0508 mm) to the shim pack
When installing an alcohol injector on an air brake system, where should it be located?! On the air intake side of the compressor After the air dryer and before the supply reservoir Between the compressor and the air dryer Above the compressor and before the air dryer
After the air dryer and before the supply reservoir
When rebuilding a clutch pack in an automatic transmission, what should be used on the piston seals during assembly?! Clean engine oil Clean transmission fluid Solvent Nothing, install seals dry
Clean transmission fluid
When LS (low sulphur) fuel is run in an engine specified for ULS (ultra-lo sulphur) which of the following components is likely to fail first?! DPF C-EGR (cooled exhaust gas recirculation) circuit Variable geometry turbocharger ECM heat exchanger
DPF
What could cause a burned synchronizer in the auxiliary of a twin counter-shaft transmission?! Damaged insert valve Improper pre-selection of range shifts Worn gear shifter linkage Defective regulator valve
Defective regulator valve
When replacing a universal joint in a multi-piece driveshaft, what should be verified during shaft reinstallation?! Driveshaft balance Driveshaft angle Driveshaft phasing Rear axle operating angle
Driveshaft phasing
What would cause scored and discoloured differential side gear thrust washers?! Incorrect gearset backlash Incorrect gearset contact pattern Extended operation with the differential lock engaged Extended wheel spinout
Extended wheel spinout
If a diesel engine is run without a thermostat, which of the following tailpipe emissions would be more likely to increase?! HC NOx Sulfur Dioxide Nitrogen Dioxide
HC
What should be done to the crown gear before attempting to install it onto the flange case half?! Freeze the crown gear Heat the crown gear to specified temperature Heat the crown gear with an oxy-acetylene torch Thoroughly lubricate the crown gear mating surface with grease
Heat the crown gear to specified temperature
When performing a 4-step injection actuation pressure test sequence on a typical HEUI (hydraulic/electronic unit injector) system, which of the following components is being tested?! Injector pressure regulator valve and high-pressure pump HEUI injection pressure Injector driver module HEUI actuation cartridge
Injector pressure regulator valve and high-pressure pump
When testing the performance of a hydraulic pump, which of the following is correct practice?! Maintain pump drive rpm as low as possible Maintain drive rpm at or above the rated rpm during the test Have the relief valve set to its lowest pressure setting Have the relief valve set to its highest pressure setting
Maintain drive rpm at or above the rated rpm during the test
Which of the following is most important when removing hydraulic cylinders from the dump section of a roll-off truck?! Drain the oil from the entire hydraulic system before removing the cylinders Disconnect the hydraulic pump from its drive Mechanically support any structure attached to the cylinders Adjust the system relief valve before removing the cylinders
Mechanically support any structure attached to the cylinders
Which of the following is an indication that an aneroid device has been shorted out on a hydromechanical highway truck diesel engine?! Increased top end power Improved lug performance Smoking at rated speed and load Puff of exhaust smoke at each upshift
Puff of exhaust smoke at each upshift
What should be done when larger than normal magnetic particles are found in the oil pan of an automatic transmission?! Clean the pan and replace the oil and filter Clean the pan and replace the oil, filter and transmission coolant Clean the pan and flush the transmission Remove, disassemble and inspect to locate the source
Remove, disassemble and inspect to locate the source
After replacing a defective EUI (electronic unit injector) with a rebuilt/exchange unit, which of the following procedures must be performed?! Replace the engine ECM Replace the personality module Reprogram new calibration codes for all 6 EUIS Reprogram a new calibration code for the replaced EUI
Reprogram a new calibration code for the replaced EUI
What would be the most likely cause of a smooth, flat fracture of a drive axle shaft?! Shock failure Fatigue failure Spinout failure Lack of lubrication
Shock failure
What could produce a twisted mainshaft in a standard transmission?! Improper driveline operating angles Not using the clutch when shifting Shock loads Excessive mainshaft gear tolerances
Shock loads
What must be removed to allow removal of a power divider?! Both axle half shafts The front driveshaft The rear driveshaft The final drive carrier assembly
The front driveshaft
What is the main advantage of installing an auxiliary power unit?! To provide constant battery charging during tractor operation To provide a fuel-efficient means to power many in-cab accessories when the truck is not operating To provide extra current during engine start-up To provide electricity for trailer reefer operation
To provide a fuel-efficient means to power many in-cab accessories when the truck is not operating
What should be performed first when removing the differential and crown gear assembly from the carrier?! Apply heat to the assembly bearings Use a punch to mark one carrier leg and bearing cup Remove the bearing adjuster rings Remove the bearing adjuster ring locks
Use a punch to mark one carrier leg and bearing cup
What is the preferred method of universal joint replacement?! Use a block of wood and a floor jack Use a hammer with the driveshaft in a vice Use a universal joint press Use sockets and a bench vice
Use a universal joint press
Which of the following best describes what occurs during a passive regeneration of a typical DPF (diesel particulate filter) on a highway truck?! Usually occurs during normal driving Requires fuel dosing in the exhaust Requires spark ignition May require the driver to pull vehicle off the highway
Usually occurs during normal driving
Which of the following hydraulic hose types would be able to accept the highest working pressure?! Fabric braided hose Wire braided hose Neoprene hose Heater hose
Wire braided hose
How is crown gear backlash measured?! With a dial indicator With a torque wrench With a vernier caliper With feeler gauges
With a dial indicator
In a standard transmission, which of the following could cause a noise in neutral?! Worn clutch release bearing Worn mainshaft rear bearing Chipped slinding gear teeth Worn or damaged speedometer gears
Worn clutch release bearing
A dump box pulsates and has a jerking motion as the lift cylinder is extended. What could be the cause?! Worn box pivot bushings Reservoir over-filled Restrictions on the high-pressure side Worn pump
Worn pump
On an air brake equipped truck that is CMVSS 121 compliant, what is the minimum air pressure before the low air warning device will activate?! 90 psi 60 psi 100 psi 120 psi
60 psi
What is the purpose of residual pressure in a hydraulic brake system?! To increase the speed of the brake application To inhibit moisture infiltrating the hydraulic fluid To increase applied brake pressure To decrease applied brake pressure
To increase the speed of the brake application
What is the purpose of residual pressure in a hydraulic brake system To increase speed of a brake application To inhibit moisture infiltrating the hydraulic system To increase applied brake pressure To decrease applied brake pressure
To inhibit moisture infiltrating the hydraulic system
If you suspect that a lead-acid battery has frozen, what should you do first?! Replace the battery Charge at high amperage Heat with a propane torch Trickle charge and observe response
Trickle charge and observe response
When load-testing a fully charged lead-acid battery at 20°C, which of the following would be the recommended load to be drawn by the carbon pile?! 1/2 of the CCA rating for 15 seconds 100% of the CCA rating for 30 seconds 1/2 of the amp/hour rating for 45 seconds 1/2 of the amp/hour rating for 15 seconds
1/2 of the CCA rating for 15 seconds
What is the reading on this 2-3" imperial micrometer?! 2.341" 2.016" 2.516" 2.041"
2.341"
Although any loose or missing bolts should be tightened or replaced when noticed, what percentage of fifth wheel mounting bracket to frame fasteners can be loose or missing before the tractor must be placed out of service?! 10% 20% 30% 40%
20%
What is the maximum inlet restriction permitted on a diesel engine air filter?! 5" H2O 10" H2O 25" H2O 50" H2O
25" H2O
On an air brake equipped truck that is CVSA compliant, what specification must be achieved when testing the compressor buildup time?! 25-120 psi in 5 minutes or less 75-100 psi in 25 seconds or less 85-100 psi in 4 minutes or less 85-100 psi in 2 minutes or less
85-100 psi in 2 minutes or less
Which of the following conditions on an air brake system could cause a high discharge of oil from the supply reservoir drain value?! Governor setting too high Governor setting too low A restricted lubricating oil return passage in the compressor Compressor drive belt slipping excessively
A restricted lubricating oil return passage in the compressor
During a PM inspection a broken radiator fan shroud is noticed. Which of the following could cause this damage?! Loose fan belts A failed fan hub clutch A broken engine mount An out of balance fan assembly
A broken engine mount
When testing a gasoline engine, what would cause a vacuum gage to produce an intermittent reading?! A burnt valve Worn piston rings A loose or leaking intake manifold gasket Worn valve guides
A burnt valve
Which of the following tools can be used to cut new external threads?! A die A thread pitch gauge A tap A thread chaser
A die
While troubleshooting an air pressure build up complaint you find no air pressure at the inlet side of the supply reservoir. What could be the cause?! A restricted air dryer Governor setting too high An empty alcohol evaporator A defective automatic discharge valve
A restricted air dryer
What would be the cause of a heavy buildup of frost at a point in the high-pressure line between the condenser and the receiver-drier?! A restriction in the line A buildup of gaseous refrigerant present in the line There is a refrigerant leak on the low-pressure side There is a refrigerant leak on the high-pressure side
A restriction in the line
What component is used to control jounce and rebound and suppress truck suspension system oscillations?! An air spring A shock absorber A leaf spring A helper spring
A shock absorber
When cutting with an oxy-acetylene torch, what should you see in the steel before depressing the cutting lever?! A small liquid puddle A change in steel colour A change in steel colour to red A change in flame colour to red
A small liquid puddle
After performing cylinder work such as boring or honing, what should be used to clean the cylinder walls?! Fresh engine oil A soap and water solution Solvent Gasoline
A soap and water solution
How are straight king pins secured to the axle on a truck's front steering axle?! A cotton pin A tapered draw key A locknut A tapered cup and cone bearing
A tapered draw key
What tool should be used to measure the air filter restriction?! A water manometer A vacuum gauge A mercury manometer A pressure gauge
A water manometer
What could cause low-pressure readings when resting a hydraulic power steering system?! A worn hydraulic steering pump A relief valve is stuck closed A restricted steering valve A bent or damaged pitman arm
A worn hydraulic steering pump
A driver complains his radio produces constant static and his newly replaced batteries are often too discharged to crank the engine. After ensuring that the batteries are fully charged, which of the following should you check first?! Alternator AC leakage Alternator amperage output Cranking motor ground integrity Battery warranty
Alternator AC leakage
What safety precautions must be followed when working on pressurized air brake components?! Always wear safety glasses and drain air pressure before dismantling components Not to worry, pressurized air is not dangerous Draining air pressure is not required before dismantling components Air pressure in a brake system is contained and cannot leak out when dismantled
Always wear safety glasses and drain air pressure before dismantling components
What type of signal does an ABS wheel speed sensor provide?! A digital signal A sinewave An AC pulse A diode
An AC pulse
What type of truck spring suspension system would be mounted above the main leaf spring assembly and only be utilized under heavy leads?! An air spring suspension A constant spring suspension An auxiliary spring suspension A coil spring suspension
An auxiliary spring suspension
What could be the problem if, while evacuating an AC system, you observe the gauges rise quickly and continue to rise until they read zero psig (zero kPa)?! Excessive moisture present in the system An external leak Restricted expansion valve Restricted evaporator
An external leak
Brake wear is uneven on only one side of the shoes. What should be checked?! Anchor pins and bushings Improper sized shoes Worn S-cam bushings ABS sensor out of adjustment
Anchor pins and bushings
What is the desired air gap between the ABS wheel speed sensor and the exciter ring?! 1/4" (6.25mm) 3/8" (9.5mm) Air gap is not critical As close as possible
As close as possible
What is the primary function of a gel-cell battery in a truck chassis battery bank?! Boosts available cranking power Powers 24V side of 12/24 system Auxiliary power source when engine is not running Stabilizes alternator output
Auxiliary power source when engine is not running
A 12-V lead-acid battery with an electrolyte temperature of 20°is voltage tested out of chassis and produces a voltage reading of 12.4 V across its terminals. Which of the following is more likely to be true?! Battery is fully discharged Battery is 50% charged Battery is nearly fully charged Battery should be replaced
Battery is 50% charged
What is the correct procedure for boring cylinders in a parent bore engine?! Bore to the new piston size plus the clearance Bore to the new piston skirt diameter Hone to the new piston size and bore to the clearance specification Bore to specified size and hone to the clearance specification
Bore to specified size and hone to the clearance specification
What voltage value should be indicated as the input terminal of a 2-wire, coolant temperature sensor in a typical truck diesel engine?! Zero V Up to 2.5 V-DC Close to 5 V-DC Between 12.6 and 14.1 V-DC
Close to 5 V-DC
which of the following methods should be observed to crank a hard-to-start, truck diesel engine?! Crank for 2 minutes, rest for 15 seconds Crank for 30 seconds, rest for 2 minutes Crank for 15 seconds, rest for 2 minutes Crank until the batteries die
Crank for 30 seconds, rest for 2 minutes
When measuring a cylinder, what is being measured by taking diameter readings at the top, middle, and bottom of ring travel?! Piston clearance Cylinder alignment Cylinder taper Cylinder out-of-round
Cylinder taper
Air pressure is higher than normal. What is the most likely problem?! Un-loader valve is stuck open Defective governor circuit Signal from supply tank Air compressor is over capacity
Defective governor circuit
How are the stator windings in a typical truck alternator configured?! Wye connection Delta connection Twisted triad Semi-elliptical
Delta connection
When servicing an air dryer what also requires replacement?! Purge valve Heater element Desiccant filter Governor
Desiccant filter
In the event that a nozzle valve is stuck open in an EHI (electro-hydraulic injector) used in a CR (common rail) fuel system, which of the following ensures that fuelling to the affected cylinder is limited?! Rail pressure sensor Unintended fuel sensor Rail pressure regulator valve Flow limited valve
Flow limited valve
When a truck has been involved in an offset front end collision, what type of frame damage would be expected?! Diamond damage Twist damage Sideway damage Sag and bow damage
Diamond damage
What specific charging system component is evaluated when you perform an AC leakage test?! Stator Field windings Diode bridge Voltage regulator
Diode bridge
When preparing to boost a set of discharged batteries on a truck chassis, where should you locate the ground clamp on the truck you are boosting?! Anywhere on the frame Alternator ground clamp Directly to a battery negative post Directly to a battery positive post
Directly to a battery negative post
When using a DMM to measure voltage, what would happen if you placed the negative terminal on the more positive section of a circuit?! Display reading would be preceded by a MINUS symbol Circuit dead short through the DMM DMM fuse failure DMM circuitboard failure
Display reading would be preceded by a MINUS symbol
What type of tubing must be used in hydraulic brake systems?! Single wall thickness steel tubing Double wall thickness steel tubing Single wall thickness copper tubing Double wall thickness copper tubing
Double wall thickness steel tubing
How is cushioning and alignment accomplished on a rubber cushion suspension system?! Drive pins are encased in rubber bushings Torque rods Saddle assembly Frame hangers
Drive pins are encased in rubber bushings
What is the proper position of hole(s) on air spring brake chambers?! At a 90° angle At a 30° angle Facing downwards, toward the road On the top, where it can be accessed
Facing downwards, toward the road
When inspecting transmission bearings, what is the cause of flaking of the bearing race?! Brinelling Fatigue Contamination Fretting
Fatigue
What condition would be present in a hydraulic system using high-viscosity hydraulic oil in a cold winter application?! High pump inlet vacuum causing cavitation High pump inlet vacuum causing aeration Low inlet vacuum causing cavitation Low inlet vacuum causing aeration
High pump inlet vacuum causing cavitation
When the inversion valve of an air brake vehicle is in effect, what does it modulate to slow the vehicle?! Holds off pressure in the spring brake chamber Directs air pressure to the service side of the dual chamber Releases stored air pressure from a separate reservoir Applies hydraulic pressure to the brakes
Holds off pressure in the spring brake chamber
In order to access any system's ECM (electronic control module) to read system faults on a truck chassis data bus, which of the following must be accessed first?! ID (message identifier) ID (subsystem identifier) ID (parameter identifier) MI (fault mode indicator)
ID (message identifier)
What is an important requirement when selecting replacement S-cams?! Identify if a left or right hand S-cam is required None, as all S-cams are identical Check for S-cam roller lubrication Test Rockwell hardness
Identify if a left or right hand S-cam is required
When installing a reinforcement plate on a truck frame, how should the bolt holes be located?! In a vertical row In a staggered bolt pattern Close to the upper frame flange Along each edge of the plate
In a staggered bolt pattern
While observing tire wear patterns and front-end alignment, which alignment angle has the potential to cause the most tire wear?! Incorrect caster angles Incorrect camber angles Incorrect king pin inclination Incorrect toe settings
Incorrect toe settings
Which of the following could occur if there was insufficient liner protrusion?! Insufficient sealing Liner flange damage would occur Over-cooling of the cylinder head The engine would overheat
Insufficient sealing
How would cavitation be identified in a disassembled hydraulic pump?! Internal components may appear to have sandblasted appearance Internal components may show a pitted or eroded type of pattern The pump housing may be cracked externally The outlet port of the pump may show a bluish colour
Internal components may show a pitted or eroded type of pattern
When rebuilding an engine with a camshaft located in the cylinder block, what would result from a failure to replace worn camshaft bearings?! Noisy valve operation Noise during high engine loads only Lower oil pressure readings Premature camshaft gear
Lower oil pressure readings
What must be done to ensure accurate main bearing oil clearance measurements during an engine rebuild?! Coat all bearing surfaces with fresh engine oil Torque the bearing cap housing the bearing being measured Measure clearances using Plastigage Allow the crankshaft to rest on V-blocks
Measure clearances using Plastigage
What should be used to lubricate the rack and slide path of a sliding fifth wheel?! All purpose grease SAE 30 engine oil Water resistant lithium based grease Mixture of light oil and diesel fuel
Mixture of light oil and diesel fuel
When adjusting a drive axle gearset, what should be done to move the contact pattern away from the crown gear tooth root?! Move the pinion away from the crown gear Move the pinion toward the crown gear Increase the gearset backlash Decrease the gearset backlash
Move the pinion away from the crown gear
At the end of an injection cycle on an engine equipped with a TP (time/pressure) fuel system, which of the following should be true?! Nozzle spring closes fuelling plunger TP tappet spring closes cup orifii Moving components of the injector are loaded into the cup with mechanical crush The cup orifii remain open and exposed to cylinder gas pressure
Moving components of the injector are loaded into the cup with mechanical crush
Which of the following is correct practice when mounting accessories to the heat-treated frame of a truck?! Never drill the web of the frame rail Never weld on the web of the frame rail Never drill or weld on the flange of the frame rail Never attach anything to the frame web
Never drill or weld on the flange of the frame rail
In an automatic transmission, what driveability problems would a stripped nylon governor drive gear cause?! Quick upshifts No upshifts High governor pressure No change to routine shifts
No upshifts
When performing repairs or service work on refrigeration components, what safety equipment should a technician wear?! Leather gloves and safety goggles Non-absorbent gloves and safety goggles Face shield and a metallic apron Safety equipment is not required
Non-absorbent gloves and safety goggles
You are measuring resistance through an NTC (negative temporary coefficient) thermistor-type temperature sensor and a reading of 75 kilo-ohms is displayed on a DMM (digital micrometer). What should be done?! Discard the sensor, resistance should be close to zero Heat the thermistor using a torch to see if resistance goes up Cool the thermistor using dry ice to see if resistance goes down Nothing. Most good thermistors test between 50 and 100 kilo-ohms resistance
Nothing. Most good thermistors test between 50 and 100 kilo-ohms resistance
When measuring circuit resistance with a DMM, what will the ohmmeter display when you place the test leads across an open circuit?! Low resistance High resistance OL Zero resistance
OL
A driver complains of truck wander when driving. What could be the cause?! Bent or twisted frame rail One or more broken leaf springs Over-inflated tires Seized spring pins
One or more broken leaf springs
On the rear of a van trailer, where should reflective (conspicuity) tape be placed?! Across the full width of the trailer base Outlining the upper corners Outlining the lower corners Up the full length of the van sides
Outlining the upper corners
What tool is generally used to measure crankshaft bearing journals?! Vernier caliper Outside micrometer Straight edge and feeler gauge "T" gauge and micrometer
Outside micrometer
What is the preferred method of running-in a rebuilt engine?! Perform a dynamometer test run Road test with service brakes applied Test driving the truck with an empty trailer Test driving the truck with a loaded trailer
Perform a dynamometer test run
What should be done before initial start-up of a rebuilt engine?! Perform a compression test Perform a cylinder leakage test Release the parking brakes Prime the lubrication system
Prime the lubrication system
When performing trailer refrigeration services, what refrigerant would most likely be used?! R-12 R-22 R-500 R-502
R-22
In the 7-way tractor trailer electrical cord, what wire colour is designated for the stop lights?! Blue Brown Red Yellow
Red
What must be performed on a truck suspension system to adjust torque rod length and drive axle alignment?! Adjust the nuts on the U-bolts Add additional spring wedges Remove or add washers (shims) Adjust the position of the spring hangers
Remove or add washers (shims)
What is the recommended method of deflating a truck tire?! Use a screwdriver to depress and hold the Schrader valve pin Remove the Schrader valve core completely Separate the bead of the tire from the rim Fracture the valve stem, allowing all of the air to escape
Remove the Schrader valve core completely
What should be done first when the spring shackle pin will not accept grease?! Replace the sping pack Replace both zerk fittings Replace the spring pins Remove weight from the spring by using a jack
Remove weight from the spring by using a jack
When preparing to lead-test a maintenance-free, lead-acid battery, the technician first checks the integral hydrometer eye and sees that it is clear. What should be done next?! Fully charge the battery before attempting to test it Replace the battery, it has a low electrolyte level Proceed with the test, the battery is fully charged Remove the surface charge, then proceed to test the battery
Replace the battery, it has a low electrolyte level
When diagnosing a leaf spring suspension complaint of harsh ride which of the following could be the cause?! Seized front spring shackle pins Tires under-inflated Broken leaf spring Inadequate fifth-wheel lubrication
Seized front spring shackle pins
What would the effect be of a brake drum that has been worn too thin?! The drum will split and crack Brakes would pull or grab Shoes and drum would heat up quickly S-cam would be unable to rotate
Shoes and drum would heat up quickly
When you are testing a diode and it conducts equally well both ways, which of the following is probably true about the state of the diode?! Forward bias Reverse bias Open Shorted
Shorted
When adjusting truck body panels, how should a door be aligned to the front fender?! Slightly inboard from the fender Slightly outward from the fender Slightly higher than the fender Slightly lower than the fender
Slightly inboard from the fender
What could cause wheel tramp?! An overload condition An under-inflated tire A broken spring pack Static unbalance of a wheel assembly
Static unbalance of a wheel assembly
A truck lead-acid battery at 20°C measures 10.5 V across its terminals. After performing a 2-minute rapid charge, the battery is disconnected from the charger and when voltage is tested across its terminals, it produces15.2 V-DC. Which of the following is the more likely explanation?! Deep cycle battery Frozen electrolyte Shorted battery plates Sulphated battery
Sulphated battery
Which of the following would be an output of the ECU (electronic control unit) of an air brake ABS (anti-lock brake system)?! The ABS indicator dash light The exciter ring The brake treadle valve The speed sensor
The ABS indicator dash light
If a coolant control valve of a HVAC unit did not close completely, what would be the result?! The AC unit would cool more than required by the temperature switch The HVAC unit would not be able to regulate the air outlet temperature The HVAC unit would not be able to control the level of air flow in the cab The AC unit would not be able to provide maximum cooling
The AC unit would not be able to provide maximum cooling
In a troubleshooting diagnostic tree, what is at the root of the tree?! Troubleshooting paths The MID Troubleshooting routes The problem
The problem
In a B-train combination which of the following relay valves would likely have the lowest crack pressure?! The front tractor axle The rear drive axle The pup axle The lead trailer axle
The pup axle
What would you suspect to be the problem if, while troubleshooting a truck's AC system you find gauge readings that are normal and line temperatures that feel correct, however vent air discharge is not cool enough?! The evaporator is obstructed by debris The AC-system has been undercharged The AC-system has been overcharged The heater valve is stuck in the open position
The heater valve is stuck in the open position
A driver explains that his low air warning device (light) has activated, but the primary and secondary pressure gauges indicate full air pressure. What could be the cause?! A faulty governor setting An air leak at the supply reservoir A fault in the air dryer circuit The low-pressure warning circuit has malfunctioned
The low-pressure warning circuit has malfunctioned
While observing a truck's air-pressure gauges when building air pressure you notice the primary reservoir is fully charged but the secondary reservoir has zero air pressure. What could be the cause?! The secondary reservoir one-way check valve is stuck open The secondary reservoir one-way check valve is stuck closed The primary reservoir one-way check valve is stuck open The primary reservoir one-way check valve is stuck closed
The secondary reservoir one-way check valve is stuck closed
When testing a truck's hydraulic steering system, what is important to achieve accurate results?! The hydraulic steering system oil should be cold The engine oil should be at operating temperature The steering system oil should be at operating temperature Hydraulic steering oil temperature is not important when testing
The steering system oil should be at operating temperature
If the air compressor governor failed to cut out, which of the following would result?! The regulator valve would stop the compressor The system safety valve would open The compressor's performance would not be affected The dash gauges would indicate normal governor cut-out pressure
The system safety valve would open
What results when the dash-mounted trailer air supply valve (red) is pulled outward (closed)?! Air is directed through the tractor protection valve The trailer air supply line is fully charged The tractor parking brakes are applied The trailer parking brakes are applied
The trailer parking brakes are applied
Which one of the following cylinder head components, when worn, would allow oil to enter the exhaust gases or intake charge?! The valve margin The valve face The valve seat The valve guide
The valve guide
What is the most likely cause of a driver complaint that the cab AC works well when first turned on, but then intermittently after extended operation?! The expansion valve is stuck in the closed position The expansion valve is stuck in the open position There is moisture present in the AC system The discharge line from the compressor is restricted
There is moisture present in the AC system
Which of the following could result from a worn cylinder counter-bore?! Excessive sleeve protrusion Upper sleeve flange separation Sleeve cavitation Piston damage during installation
Upper sleeve flange separation
When testing the amperage output of a heavy-duty truck alternator using an amp clamp, which of the following methods should be used to draw the specified load from the alternator?! Turn on all the lights on the rig Crank the engine for 15 seconds Use a carbon pile Create a temporary short at the starter solenoid
Use a carbon pile
When troubleshooting a complaint of sluggish cranking on a truck with batteries that test ok, you observe that one of the battery ground posts is abnormally hot. Which of the following should be performed first?! Test for high resistance at the starter motor positive terminal Voltage drop test across battery cable clamp and post Remove starter motor and check for high resistance at hold in windings Voltage drop test across the insulated battery to starter cable
Voltage drop test across the insulated battery to starter cable
When an alternator is full-fielded, which of the following temporarily ceases to function?! Rectifier Rotor magnetic field Voltage regulator Stator
Voltage regulator
What type of output would you measure from a throttle position sensor described as "non-contact"?! WM (pulse width modulation). DC analogue AC analogue 3-phase ripple
WM (pulse width modulation)
When will the ride height control valve supply more air to the air springs?! When more load is applied to the truck When less load is applied to the truck When uneven terrain is encountered When the compressor begins its loaded cycle
When more load is applied to the truck
When is crankshaft noise more noticeable?! When the engine is cold When the engine is at low idle When the engine is hot The noise should not change with temperature or rpm
When the engine is hot
What condition could affect ride height when inspecting spring equalizers on a tandem axle air suspension system?! A leaking air spring A torque rod that is out of adjustment Worn equalizer bushings A tie rod that is out of adjustment
Worn equalizer bushings
During a cylinder leakage test, what would be the cause of air escaping from the oil fill port?! Worn or weak piston rings A burnt or poor sealing exhaust valve A burnt or poor sealing intake valve Cylinder liner cavitation
Worn or weak piston rings
When performing a dry compression test on a gasoline, what would cause low compression readings to significantly rise during a wet compression test?! Burnt valves Worn piston rings Defective head gasket Worn valve guides
Worn piston rings
During a PM inspection the steering wheel binds when turned. What could cause this condition?! Excessive sector gear to ball nut clearance in the steering gear Worn king pin bushings Worn steering shaft universal joints Worn tie rod ends
Worn steering shaft universal joints
If you have accessed an OEM (original equipment manufacturer) data hub, which of the following must be true?! You are connected to the truck data bus You are connected to a data bus MID You are viewing FMIs You are on-line
You are on-line
