Final Drive Part 1 Flashcards
What are the three functions of the final drive axel assembly?
- It multiplies the torque from the transmission
- It changes the direction of power flow by 90 degrees
- It allows the drive wheels to turn at different speeds while cornering
The final drive axel assembly changes the power flow by ____ degrees.
90
What is responsible for allowing the wheels to turn at different speeds while cornering?
The final drive axle assembly
What are the three components of the RWD live axel?
- Rear axle housing
- Final drive gears
- Differential gears
What is the function of the differential gears?
Allows the wheels to turn at different speeds
What is the function of the rear axle housing?
Houses components and supports suspension
What are the two functions of the final drive gears?
Multiplies torque and transfers power 90 degrees to the wheels
What safety measures should you use when operating a hydraulic press?
Wear full face protection and safety boots
When removing some gears and bearings you may need the use of ___________
Bearing separators and pressure screw pullers
Since you should never use an impact wrench to tighten or loosen a pinion nut, what should you use?
Drive yoke holding tool
What is the purpose of a pinion depth gauge?
To measure the position of the drive pinion compared to OEM specs
What do you use to measure ring gear backlash, axle flange runout, ring gear runout and more?
Dial indicator
What is gear marking compound used for?
To check tooth contact patterns
What are the three functions of gears?
- Transmit force
- Multiply or decrease torque
- Increase or decrease speed
Which type of gear has straight teeth, is noisy and is used for transmissions?
Spur gears
Which type of gears have angled teeth, are stronger than spur gears, operate quietly, produce side thrust and are used as final drive gears in a transaxle?
Helical Gears
Which gears transmit torque over a 90 degree angle?
Plain bevel gears
What is the equation used to calculate torque?
Force x radius
What is unit is torque measured in?
ft-lbs (pound feet) or Nm (Newton meters)
When a small gear drives a big gear, torque is __________ by the larger gear’s radius.
Increased
2x radius = 2x ________
torque
The equation to find gear ratio is: Gear ratio = ___________
Driven gear teeth/drive gear teeth
If the gear ratio is 10:1, is this a reduction or overdrive?
Reduction
If the gear ratio is 30/60 or 0.5:1, is this overdrive or reduction?
Overdrive
If the gear ratio is 3:1, what is happening to the output gear speed?
Decreasing
What is happening to the output gear speed when the gear ratio is 0.25:1?
Increasing
Would you want a high or low numerical gear ratio for more towing power?
High
Would you want a high or low numerical gear ratio for higher road speed?
Low
Which type of gearset uses whole numbers in its ratio and must use index marks when being re-assembled?
Non-hunting final drive gearset
Which gearset has a gear ratio which causes a drive pinion gear tooth to contact the same ring gear teeth over 2 or 3 revolutions?
Partial non-hunting final drive gearset
Which gearset has a ratio that causes a pinion gear tooth to contact all ring gear teeth before it meets the same tooth again?
Hunting final drive gearset
Which gearset could have a ratio of 2.75:1 and does not need to be marked for reassembly?
Hunting final drive gearset
The _______ is found on the rear axle stamp or tag or on the vehicle certification label.
axle code
How would you determine the gear ratio without removing cover?
- compare the wheel rotation to driveshaft rotation
or - divide ring gear teeth by pinion teeth
What is the overall drivetrain ratio if the transmission gear ratio is 2:1 and the final drive gear ratio is 5:1?
10:1
What is the advantage of using a hypoid final drive gearset?
- Since the drive pinion gear is below the ring gear, the drive shaft and body can be lower
- Reduced driveline tunnel in the floor allows more passenger room
What is the purpose of the differential gear assembly?
Allows the drive wheels to turn at different speeds when required
What is a differential made up of?
4 differential gears (2 pinions and 2 side gears) located inside a gear case
When would a pinion gear walk around the slower moving side gear and transfer more speed to the outside wheel?
While turning
When would each wheel rotate at 100% of case speed with the differential case driving the pinion shaft end over end?
While driving straight