Differentials & Final Drive Assemblies Flashcards
What are 3 purposes of the differential?
rotate power 90 degrees, increase torque, allow tires to turn at different speeds
What part does the driveshaft bolt on to?
pinion flange or companion flange
What does a salisbury axle have that a banjo doesn’t?
cover
What is the name of the part that gets removed from a banjo differential as an assembly?
pumkin
Power goes from the case to what component next?
pinion shaft
What type of bolts hold the ring gear to the case?
Grade 8 left hand threads bolts
What component houses the differential in a FWD vehicle?
transaxle
What will determine the type and size of the differential installed in a truck?
transmission, engine, weight, towing, loads & size
What are the different types of LSDs?
gear, viscous, electronic, locking, clutch
What is an advantage of an LSD over and open differential?
prevents tire slip
What type of differential has an internally mounted gear assembly?
Salisbury (integral)
What type of differential has removable gear assembly?
Banjo (removable carrier)
Describe the power flow of the differential
drive pinion gear -> ring gear -> case -> pinion gears -> side gears -> axle
What is a Hypoid Gear?
Teeth are cut on an angle and gears meshes below center line
How much pressure can build up between the pinion gear and ring gear?
400,000PSI
How often do you change the fluid on an open differential?
50,000 kms
How often do you change the fluid on an Limited Slip differential?
25,000 kms
What is the max fill on a differential?
half an inch from bottom of fill hole
How often can you reuse a crush sleeve?
Just once!
How tight should the pinion bearing preload be?
15 - 25 ft.lbs
What is a semi floating axle?
Weight of the vehicle goes through the axle bearing
What is a full floating axle?
Weight of the vehicle does not go through the axle bearing
What is the gear ratio of the final drive called?
axle ratio
How do you determine Axle Ratio
divide the number of teeth on the ring gear by the number of teeth on the drive pinion gear
What are the characteristics of a Growl Noise? (coming from the Differential)
- low frequency sound
- constant in intensity
- not torque sensitive
- can be heard through all speed ranges.
What are the characteristics of a Howl Noise? (coming from the Differential)
- medium frequency sound
- rhythmic oscillation
- can be heard through all speed ranges
- torque sensitive
What are the characteristics of a Whine Noise? (coming from the Differential)
- high frequency sound
- no oscillation
- sharp metallic quality
- speed, torque & load sensitive
What type of noise would be made with excessive runout of rotating parts on a differential?
Howl Noise
What type of noise would be made from a bearing issue in a differential?
Growl Nosie
What type of noise would be the result of a ring and pinion gear issue in the differential?
Whine Noise
During a differential pinion and ring gear pattern test, what is the condition when the markings on both drive and coast sides are towards the heel?
Pinion Depth is correct & backlash incorrect (to much clearance)
During differential pinion and ring gear pattern test, what is the condition when the markings on both drive and coast sides are towards the toe?
Pinion Depth is correct & backlash incorrect (to little clearance)
What type of ring gear has the toe and heel equal in size?
Face Hobbed (2-cut)
What type of ring gear has the toe shorter then the heel?
Face Milled (5-cut)
What design drive pinion uses 3 bearings
Straddled
What design drive pinion uses 2 bearings?
Overhung
With which type of differential gear set does the pinion gear teeth contact every ring gear tooth?
Hunting Gear Sets
What type of differential gear set cannot be reduced any further?
Hunting Gear Set
What type of differential gear set end in a whole number?
Non-hunting Gear Set
With which type of differential gear set does the pinion gear tooth only contact a few ring gear teeth during each revolution?
Non-hunting Gear Sets
With which type of differential gear set does the pinion gear teeth need more then 1 revolution to contact the highest number of ring gear teeth
Partially Non-hunting Gear Sets
What type of differential gear set end in .20, .25, .50 or .75?
Partially Non-hunting Gear Set
