© 2012 Delmar, Cengage Learning Front-Wheel-Drive (Transaxle and CV Joint) Service Chapter 78.
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Transcript of © 2012 Delmar, Cengage Learning Front-Wheel-Drive (Transaxle and CV Joint) Service Chapter 78.
© 2012 Delmar, Cengage Learning
Objectives• Diagnose CV joint problems• Service CV joints• Replace CV joint boots• Disassemble and repair transaxles
© 2012 Delmar, Cengage Learning
Introduction• Removal, service, and replacement of front
drive axles and constant velocity (CV) joint– Lucrative service area
• Transaxle removal – Relatively straightforward
• Once axle removal is accomplished
© 2012 Delmar, Cengage Learning
Transaxle and Front-Wheel-Drive Service and Repair
• Checks of the axle assemblies – Some can be made with the axle on the car
© 2012 Delmar, Cengage Learning
Leaking CV Joint Boot• Front-wheel-drive axles
– Require service as a vehicle ages
– Some checks and services can be made with axle on vehicle
• Others require removal and disassembly of components
© 2012 Delmar, Cengage Learning
CV Joint Boot Service• Boots age over time
– Repeated flexing and exposure to elements
• Boot fails– Grease leaks out
– If not replaced: entire joint will fail
– Most common problem with CV joints
• Replacement boot kits– Come with new clamps and correct amount of
high pressure grease
© 2012 Delmar, Cengage Learning
Axle Inspection and Diagnosis• Check halfshaft for obvious looseness
– Noises can be detected from the test drive
– Weight must be on the suspension when checking for a noise
• Questions to ask customer:– What does the noise sound like?
– Does it occur during acceleration, deceleration, or when turning?
© 2012 Delmar, Cengage Learning
CV Joint Diagnosis• Clicking sound during a turn
– Indicates bad outboard joint
– Always check the splines on a shaft
• Bad plunge joint makes clunking sound– Starting from a stop
– During deceleration
– Braking
• Excess wear – Hard to detect visually
© 2012 Delmar, Cengage Learning
Axle Shaft Removal• Major steps
– Loosen axle nut
– Remove the stub shaft from the hub
– Remove the stub shaft
– Remove the axle
– Remove snap rings and clips
– Remove boot
© 2012 Delmar, Cengage Learning
CV Joint Replacement• Internal circlip
– Common way of retaining a fixed joint to shaft
– Called knock-off-type joint
– Different version used in some Japanese vehicles
• CV joint has been removed from axle– Boot is removed
• Fixed Rzeppa joints – Held to their shafts by external snap ring or
internal clip
© 2012 Delmar, Cengage Learning
Fixed Joint Disassembly and Inspection
• Major steps– Use drift punch to move inner race to the side for
a more complete inspection• Wipe the parts off and look for wear
– Disassemble Rzeppa joint• Mark all major components• Remove the balls• Wipe and lightly grease
– Install the boot and joint
© 2012 Delmar, Cengage Learning
CV Joint Boot Clamps• Several types
– Universal clamp
– Bridge-type clamp
– Earless clamp
– Pressed-fit ring
• Installing small-end clamp– Pull big end of the boot over CV joint and install
retaining clamp
– Vent the small end of the boot
© 2012 Delmar, Cengage Learning
Servicing an Inner Tripod Joint• Major steps
– Before removing: tape shaft and joint
– Cut away the clamps and boot
– Check to see if tripod rollers come off of spider
– Inspect condition of inside tulip
– Align any marks
– After boot and tripod are reinstalled: grease rollers and fill boot with rest of grease
© 2012 Delmar, Cengage Learning
Double Offset Plunge Joints• Vary in how they are connected to axle shaft
– Most held by internal circlip• Joint must be disassembled before it can be
removed
– Other kind has a circlip that can be removed by pounding on outer housing
• Metal retaining ring holds parts in the housing
© 2012 Delmar, Cengage Learning
Cross Groove Joint Serviceand Rebuilt Halfshafts
• Key points– Cross groove joint is serviced in similar manner
to Rzeppa joints• Disassembled by turning inner race and cage
perpendicular to outer cage and removing them
– Complete rebuilt halfshaft is a popular repair• Installing rebuilt halfshafts is often in the best
interest of the customer
© 2012 Delmar, Cengage Learning
Installing the Axle• Major steps
– To install a spline-type joint into transaxle: push in on axle while turning it to align splines
– After inner end is installed: position stub shaft into hub as far as it can go
– Do not forget to torque ball joint stud bolt
– When vehicle is back on ground: torque new stub shaft nut
– Check clearance of boot clamps before test-driving
© 2012 Delmar, Cengage Learning
Transaxle Repair and Removal• Key points
– Transaxles used with transverse engines• Differential gears are helical gears• No pinion depth or backlash adjustments
– Front-wheel-drive vehicles • Easier to pull engine with transaxle• Support the engine if it is easier to leave it in the
vehicle • Unbolt transaxle from engine• Axles are pulled in manner previously described
© 2012 Delmar, Cengage Learning
Manual Transaxle Repair• Key points
– Separate halves of case on a transaxle
– Check service manual for any specifics
– Service and assembly are similar to RWD transmissions
– End play of gears is checked with feeler gauge or dial indicator
– Thrust washers, shims, or snap rings can be used to make adjustments
© 2012 Delmar, Cengage Learning
Automatic Transaxle Repair• Automatic transaxle repair
– Same as RWD automatic transmissions
• Differences– Gar or a chain is driven by transmission output
shaft to turn differential section
– Automatic transaxles have a differential
© 2012 Delmar, Cengage Learning
Transaxle Differential Side Bearing Adjustment
• Case halves are reassembled– Differential side
bearing preload is adjusted
• Some use special tools