© 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

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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

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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

© 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

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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

© 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

© 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

© 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

© 2012 Delmar, Cengage Learning

Install the Transaxle• Installation of transaxle is the reverse of

removal sequence– After installation: be sure to check transaxle

lubricant level• Some have a fill plug on the side• Some have a dipstick• Others require removal of speedometer gear