Heavy Duty Truck Systems TRANSMISSIONS

When measuring the total indicated runout (TIR) of a driveshaft, you record 0.003" (0.008 mm) positive and 0.005" (0.13 mm) negative through one shaft revolution. What is the TIR?

0.008 inch (0.21 mm)

Which of the following dimensions would be a typical specified clearance on a pull type clutch between the fork fingers and the throw out bearing in a clutch pack using a clutch brake?

1/8 inch

Which of the following driveshaft tube ratings would be most common in linehaul highway tractors?

1700 series

Which of the following transmission gear ratios reduces transmission output shaft speed the most?

3.60:1

Which of the following dimensions would be the specified clearance between a release bearing and a clutch cover in a clutch pack with no clutch brake?

3/4 inch

Which of the following operating conditions would require the most frequent lubrication of the driveshaft?

4x4 vocational off-highway

Which of the following transmission gear ratios would permit the greatest torque output to the drivetrain?

5.36:1

If a force of 25 pounds is applied perpendicular to the centerline of a shaft, two feet from its centerline, how much torque is produced?

50 pound feet

What is a typical air pressure regulator specification for the pneumatics on a Road Ranger compounded truck transmission?

60 psi

Technician A says excessive clutch pedal free travel can result in a clutch that does not fully disengage. Technician B says that too little free pedal travel can result in a slipping clutch. Who is correct?

Both A and B

Technician A says that a Solo clutch should automatically adjust for the life of the clutch pack. Technician B says any clutch using a lock strap to set the adjusting ring, must be periodically adjusted. Who is correct?

Both A and B

Technician A says that a flywheel can be machined (resurfaced) as long as the maximum allowable tolerances specifications are adhered to.. Technician B says that a clutch pressure plate with warpage sufficient to insert a 0.010 inch thickness gauge under a straight edge must be replaced. Who is correct?

Both A and B

Technician A says that anything that rotates, requires torque to make it turn. Technician B says that torque is calculated by multiplying applied force by its distance from the centerline of rotation. Who is correct?

Both A and B

Technician A says that clutch shaft pilot bearings should be replaced each time a clutch pack is replaced. Technician B says that the flywheel should always be inspected when a clutch pack is replaced. Who is correct?

Both A and B

Technician A says that during the coupling phase, the impeller and turbine should be turning within 10% of the same speed. Technician B says that the only time that the impeller and turbine turn at exactly the same speed in when the lock-up clutch is engaged. Who is correct?

Both A and B

Technician A says that to properly lubricate a driveshaft U-joint with twin zerks, grease must be pumped into both nipples. Technician B says that if grease exits all four trunnion seals on a U-joint, it indicates that it has been properly greased and purged. Who is correct?

Both A and B

When installing a 15 1/2-inch clutch assembly, Technician A uses guide studs installed in the flywheel to support the weight. Technician B uses a splined pilot shaft when installing both 14- and 15 1/2-inch clutch assemblies. Who is correct?

Both A and B

When referencing a triple-countershaft transmission, which of the following is true?

Input torque is split 3 ways

A driveshaft U-joint has failed. Technician A says that the complete driveshaft assembly should be removed from the chassis to replace the U-joint. Technician B says that the driveshaft must be separated at the slip spline to make the repair. Who is correct?

Neither A nor B

Technician A say that driveshaft U-joints are expensive and engineered to last the life of the vehicle. Technician B says that a 1600 Series driveshaft is the heaviest available for linehaul highway trucks. Who is correct?

Neither A nor B

Technician A says that a clutch is fully disengaged when the pedal is all the way up. Technician B says a clutch is engaged when the clutch pedal is moved from fully released to full travel to the floor. Who is correct?

Neither A nor B

Technician A says that a driveshaft with U-joints speeds up and slows down once per rotation. Technician B says that to avoid torsional vibrations, the rear U-joint needs to cancel out the non-uniform rotation of the forward U-joint. Who is correct?

Neither A nor B

Technician A says that a torque converter stator has a direct mechanical connection to the impeller. Technician B says that a torque converter stator has a direct mechanical connection with the turbine. Who is correct?

Neither A nor B

Technician A says that all heavy-duty trucks with automatic transmissions use centrifugal lock-up clutch's. Technician B says that a centrifugal lock-up clutch consists of a belt, clutch plate, and back plate. Who is correct?

Neither A nor B

Technician A says that automated manual transmissions (AMTs) no longer require clutches. Technician B says that two-pedal AMTs have eliminated the clutch from the drivetrain. Who is correct?

Neither A nor B

Technician A says that when a torque converter flex plate is used on a larger diesel automatic transmission, a flywheel is never required. Technician B says that when a flex plate is used, the starter motor pinion engages with teeth on the converter housing. Who is correct?

Neither A nor B

Which of the below listed clutch's do not require routine adjustments.

Solo

Technician A says that a Road Ranger 18-speed transmission uses a five-speed main box using identical principles to that in a 10-speed transmission. Technician B says that a Road Ranger 18-speed transmission uses twin compounds, one located in front of, the other behind, the main section. Who is correct?

Technician A only

Technician A says that a driveshaft with U-joints speeds up and slows down twice per full rotation. Technician B says that to minimize torsional vibrations, U-joint working angles should be set as high as possible. Who is correct?

Technician A only

Technician A says that center (intermediate) plate binding on its drive pins can cause clutch release problems on a 14-inch clutch pack. Technician B says that it is a common shop practice to replace the friction facings on clutch discs when they wear out. Who is correct?

Technician A only

Technician A says that in any type of fluid coupling not equipped with a mechanical lock-up some slippage exists resulting in a difference between input and output speeds. Technician B says that in torque converter with a lock OUT clutch, the coupling phaseimpeller and turbine rpms match. Who is correct?

Technician A only

Technician A says that the main shaft and countershafts in twin and triple countershaft transmissions are mounted parallel to each other. Technician B says that the main shafts and counter shafts are not mounted parallel to each other. Who is correct?

Technician A only

Technician A says that the torque load in a multiple countershaft transmission is distributed evenly through the countershafts. Technician B says that most heavy-duty truck transmissions use a triple countershaft design. Who is correct?

Technician A only

Technician A says that when it is necessary to repair a torque converter stator assembly, it must be removed first. Technician B says that cracked stator vanes can be TIG welded. Who is correct?

Technician A only

Technician A says that as driveshafts speeds increase, permissible U-joint working angles also increase due to centrifugal force. Technician B says that when a truck diesel engine produces 1,000 lb-ft of torque that is multiplied by a 10:1 transmission gear ratio, 10,000 lb-ft of torque must pass through the driveshaft. Who is correct?

Technician B only

Technician A says that coasting when a clutch is disengaged can cause engine overspeed. Technician B says that coasting with a clutch disengaged can spin the driven discs at speeds as high as 10,000 rpm due to the multiplication of drivetrain ratios. Who is correct?

Technician B only

Technician A says that most gearing used in a typical truck transmission when torque is reduced and speed is increased. Technician B says that when a standard transmission is in 1:1 ratio, the engine flywheel and the transmission tail shaft should rotate at the same speed. Who is correct?

Technician B only

Technician A says that when a clutch brake is damaged by driver abuse, the transmission must be removed to install a replacement clutch brake. Technician B says that a two-piece clutch brake can be used as a replacement for an integral brake. Who is correct?

Technician B only

When a fault code is logged on a AMT transmission, the electronics are designed to _______________.

a fall back mode

Which of the following is the closest to the outside diameter on a gear tooth?

addendum

What factors determine the required driveshaft diameter and wall thickness?

all of the above

Which of the following components are located on the drive side (as opposed to the driven side) of a clutch pack assembly?

all of the above

Which of the following would represent ideal operating conditions for a pair of universal joints on a propeller shaft?

all of the above

Which of the following is a function of the slip yoke used on a driveshaft?

allows the driveshaft to change length as differential carrier operating angle changes

Which type of clutch pressure plate design provides a constant plate load as the friction faces wear?

angle spring, pull-type/diaphragm spring, pull-type clutch

Which of the following is recommended to be applied to the exterior of a set of U-joint bearing caps before installation into the yokes?

anti-seize compound

From the list below, which would be components needing to be inspected when replacing a clutch? choose all that apply.

bell housing mounting face, transmission input shaft and seal, pilot bearing

When a truck transmission uses helical gearing, which of the following has to be true?

both right-hand and left-hand gears must be used

Which of the following would most likely result if the intermediate plate drive pins in a pot type flywheel housing are not properly aligned?

clutch hangs-up on release

When the impeller and turbine speeds are turning within 10% of each other, this is known as:

coupling phase

Choose from the list below what might we see if a clutch on a class 8 truck has been slipping from improper adjustment?

cracks in the flywheel face, heat marks on the flywheel and center disk, excessively worn clutch plates

Which type of clutch discs would best suit a linehaul truck with a high torque rise engine?

dampened disc with ceramic facings

A truck that operates occasionally off road would need a _____________ transmission to be able to power through soft ground conditions?

deep reduction

Backlash between drive gears can be measured using a ______________.

dial indicator

What instrument should be used to measure driveshaft runout?

dial indicator

A flex plate can also be known as a flex.......

disc

When adjusting a pull type clutch, the brake pedal should be ___________________.

doesn't matter

If a truck transmission is described as being non-synchronized, which of the following is a recommended driving technique?

double-clutching

What determines the point at which a centrifugal clutch becomes fully engaged?

engine rpm

Which of the following does most to determine the power output of a torque converter?

engine rpm

What is generally considered to be the major cause of clutch failure?

excess heat

When two gears are running with excessive out of spec. gear lash, choose from the list below problems that could occur.

excessive gear noise, total gear failure, chipped gear teeth, excessive gear wear

Which of the following components can be used to transfer engine crankshaft torque to the torque converter assembly?

flex plate

When is vortex flow at its maximum during torque converter operation?

full turbine stall

Where should the clutch pedal be positioned while the internal adjusting ring of a pull-type clutch is being turned during a clutch adjustment?

fully depressed

When will torque multiplication be the greatest?

greatest difference between pump and turbine rpm

If a drive gear is required to rotate a driven gear in the same direction of rotation, which of the following is a requirement?

idler gear is required between the drive and driven gears

A gear of 12 inches in diameter is driving a second of 24 inches in diameter. Which of the following will result from the driven gear?

increased torque, reduced speed

Which of the following methods can be used to adjust drive carrier operating angle when correcting driveline angles on a truck with a leaf spring rear suspension?

install axle shim wedges

What is the reason that a gear climbing condition tends to be short-lived?

it creates a new tooth contact pattern

Why is backlash required between meshing gears?

limits coasting whine, controls climbing, allows for heat expansion and lubrication of gears

Which of the following are recommended lubricants for heavy-duty truck U-joints?

lithium-based grease with EP additives + NLGI grade 1 or 2 grease

When greasing a driveshaft U-joint, grease exit from three trunnion seals but not the fourth. What should be done next?

loosen the bearing cap on the affected trunnion and try again

In a standard Road Ranger transmission, which of the following components could be described as floating?

mainshaft

Which of the following could cause the clutch center plate to hang-up?

misaligned intermediate plate drive pins

When after pressing the clutch pedal to the floor on a class 8 truck with a pull type manual clutch, a driver is not able to put the truck into gear with the engine running. Which answer below correctly describes what would be the problem?

missing clutch brake assembly

Which of the following BEST describes the role of the auxiliary section in a truck standard transmission?

multiplies the available gear ratios

Which of the following is a disadvantage of spur gearsets?

noise

Which of the following bad driving practices is the most likely cause for clutch facings to be "thrown off" the clutch discs?

over speeding from coasting

What is an auxiliary drive system for chassis accessories such as hydraulic pumps driven by the transmission known as?

power-takeoff (PTO)

What is another term used to describe the impeller used on a torque converter?

pump

When lubricating universal joints, which of the following is best practice?

pump grease until it exits from all four trunnion seals

Where is the range shift cylinder located on a standard twin countershaft transmission with an auxiliary section?

rear of the auxiliary section

Which of the following is NOT an advantage of helical gears?

reduces thrust forces

What type of stator tends to be found in heavy-duty truck torque converters?

rotating

What is used on a driveline hanger bearing to buffer driveshaft vibrations and road shock?

rubber insulators

Which of the following valves make the low- or the high-range sections of a range cylinder shift?

slave valve

Which of the following components consists of a hardened, splined stub, welded to the end of a driveshaft tube, and mates to a yoke with matching internal splines?

slip yoke

What is the function of the clutch brake?

smooth shifts into first and reverse

When chips and flakes of metal separate from a U-joint trunnion race due to metal fatigue, how would the failure be categorized?

spalling

A gear with teeth machined straight and parallel to the shaft on which they are mounted are known as:

spur gear

Which of the following driving practices can cause abnormal wear to clutch components?

standing starts in high gear ratios, riding the clutch pedal, using the clutch to hold a truck on an incline

When a gear with 14 teeth drives a gear with 21 teeth, how will speed and torque output be changed?

torque increases, speed decreases

How many countershafts are used in the forward section of a RoadRanger transmission?

two

Which of the following methods of separating a U-joint from a driveshaft yoke when it is on the truck, is recommended?

two-jaw U-joint puller

Which of the following components contains a forged journal cross and trunnions?

universal joint

In which of the following phases of torque converter operation will torque be multiplied?

vortex flow

When the Urge-to-move feature is used on an Eaton Auto shift with an AW clutch, what hardware component in the system makes this possible?

wet clutch

Which of the following descries a broken back driveline arrangement?

working angles of its U-joints are equal + companion flanges or yokes are not parallel

Which of the following terms is another way of describing a U-joint cross?

yoke