Find the cause of the problem.
Compare the inspection and road test results with the following chart.
Use the following diagnostic routine chart to identify the probable cause and know what corrective actions should be taken to repair the component/vehicle and to prevent a reoccurrence.
Diagnostic Routine Chart
Condition Action
· Fluid loss
· GO to Diagnostic Routine — Fluid Loss
· Noise louder on turns (sweeping turn)
· GO to Diagnostic Routine — Noise Louder on Turns (Sweeping)
· Axle noise (growl)a in tight turn
· GO to Diagnostic Routine — Noise (Growl) In Tight Turn
· Axle noise (chatter/shudder)a in tight turn, limited slip differential
· GO to Diagnostic Routine — Noise (Chatter/Shudder) In Tight Turns, Limited Slip Differential
· Axle noise (whine)a in all or more than one drive mode
· GO to Diagnostic Routine — Noise (Whine) In All Or More Than One Drive Modes
· Axle noise (tick/click)a in all or more than one drive mode (drive, cruise, coast)
· GO to Diagnostic Routine — Noise (Tick/Click) In All Or More Than One Drive Modes
· Axle noise (howl/moan)a in all or more than one drive mode (drive, cruise, coast)
· GO to Diagnostic Routine — Noise (Howl/Moan) In All Or More Than One Drive Modes
· Axle noise (clunk)a on changes in speed or direction of power
· GO to Diagnostic Routine — Noise (Clunk) On Changes In Speed Or Direction Of Power
· Front axle will not engage/disengage
· GO to Diagnostic Routine — Front Axle Will Not Engage/Disengage
· Vibration
· For additional information on driveline vibration diagnostics, REFER to Section 100-04.
Refer to Section 100-04 for a glossary of noise-related terms.
NOTE: If the conclusion of the road test points to an axle assembly section (ring and pinion or differential case) concern, carry out a visual inspection of the rear axle.
Inspect the axle components.
Remove the axle assembly.
Remove the differential housing cover. Drain the axle lubricant through a white cloth. Check the fluid for:
any foreign material.
metal particles.
burnt odor.
NOTE: When inspecting the axle, do not clean the components immediately. Cleaning may remove diagnostic evidence.
Inspect the axle components.
Look for:
loose fasteners.
notches or visible steps or grooves created by wear.
pitting or cracking along gear contact lines.
scuffing or deformations.
discolorations.
nicks or ridges on gear teeth.
Clean the axle components for inspection.
Remove as much lubricant as possible with clean solvent. Wipe the components or blow them dry with compressed air.
Re-inspect for:
loose fasteners.
notches or visible steps or grooves created by wear.
pitting or cracking along gear contact lines.
scuffing or deformations.
discolorations.
nicks or ridges on gear teeth.
Check backlash and carry out a ring and pinion pattern test. Refer to Checking Differential Ring Gear Backlash and Checking Tooth Contact Pattern and Condition of the Ring and Pinion in this section.
Diagnostic Routines
Diagnostic Routine — Fluid Loss
Possible Component Reference/Action
· Vent
· CLEAN the axle vent and vent hose.
· Overfilled axle
· CHECK the lubricant level for specific amount.
· Fill plug
· CLEAN the area around the plug. REMOVE the plug. APPLY pipe sealant and INSTALL the plug.
· Halfshaft oil seal
· INSTALL a new halfshaft oil seal.
· Pinion seal
· INSTALL a new pinion seal.
· Differential housing cover
· RESEAL the differential housing cover.