Section 05-02F: Differential, Dana Model 80 Locking Axle
1996 F-350 Super Duty Workshop Manual
DIAGNOSIS AND TESTING

Symptom Chart — Detroit Locker® Differential

DETROIT LOCKER® DIFFERENTIAL
ConditionPossible SourceAction
  • Hub Studs Shearing; Rear Tire Scuffing; Axle Shaft Breakage
  • Improper installation; damaged differential.
  • PERFORM installation test.
 
  • Overloading or improper weight distribution.
  • REMOVE excess weight and REDISTRIBUTE the load from side to side, according to the vehicle/axle manufacturer's instructions.
 
  • Bent axle shaft or housing; axle shafts on different center lines.
  • REPLACE bent axle shafts or housing, or REALIGN hub faces and bolt circles in both the differential carrier and axle housing.
 
  • Worn or damaged axle components.
  • CHECK the condition of the ring gear, pinion gear, bearings, seals, etc. REPLACE as required.
 
  • Foreign matter in axle housing or improper assembly of axle components.
  • INSPECT for contamination. CHECK assembly of axle components.
  • Steering Difficulty; Vehicle Pulls on Straight Forward Driving or Tends to Go Straight When Making Turns
  • Improper installation; damaged differential.
  • PERFORM installation test.
 
  • Overloading or improper weight distribution.
  • REMOVE excess weight and REDISTRIBUTE the load from side to side, according to the vehicle/axle manufacturer's instructions.
 
  • Unequal rolling radii of the drive wheel.
  • REPLACE tires or ADJUST tire pressures until rolling radii are equal.
 
  • Broken axle shaft.
  • REPLACE axle shaft.
 
  • Bent axle shaft or housing; axle shafts on different centerlines.
  • REPLACE bent axle shafts or housing, or REALIGN hub faces and bolt circles in both the differential carrier and axle housing.
 
  • Incorrect wheel alignment.
  • CORRECT as required. Refer to appropriate Group 04 section.
 
  • Worn or damaged axle components.
  • CHECK the condition of the ring gear, pinion gear, bearings, seals, etc. REPLACE as required.
  • No Differential Action; Binding in Turns
  • Improper installation; damaged differential.
  • PERFORM Installation Test.
 
  • Broken axle shaft.
  • REPLACE axle shaft.
 
  • Bent axle shaft or housing; axle shafts on different centerlines.
  • REPLACE bent axle shafts or housing or REALIGN hub faces and bolt circles in both the differential carrier and axle housing.
 
  • Foreign matter in axle housing or improper assembly of axle components.
  • INSPECT for contamination. CHECK assembly of axle components.
  • Excessive Driveline Noise

    NOTE: Detroit Locker® differentials will emit "metallic" sounds due to backlash built into the unit. This is normal.

  • Improper installation; damaged differential.
  • PERFORM Installation Test.
 
  • Overloading or improper weight distribution.
  • REMOVE excess weight and REDISTRIBUTE the load from side to side according to the vehicle/axle manufacturer's instructions.
 
  • Unequal rolling radii of the drive wheel.
  • REPLACE tires or ADJUST tire pressures until rolling radii are equal.
 
  • Broken axle shaft.
  • REPLACE axle shaft.
 
  • Bent axle shaft or housing; axle shafts on different centerlines.
  • REPLACE bent axle shafts or housing or REALIGN hub faces and bolt circles in both the differential carrier and axle housing.
 
  • Incorrect wheel alignment.
  • CORRECT as required. REFER to appropriate Group 04 section.
 
  • Foreign matter in axle housing or improper assembly of axle components.
  • INSPECT for contamination. CHECK assembly of axle components.
  • Excessive Tire Wear
  • Improper installation; damaged differential.
  • PERFORM Installation Test.
 
  • Overloading or improper weight distribution.
  • REMOVE excess weight and REDISTRIBUTE the load from side to side according to the vehicle/axle manufacturer's instructions.
 
  • Unequal rolling radii of the drive wheel.
  • REPLACE tires or ADJUST tire pressures until rolling radii are equal.
 
  • Broken axle shaft.
  • REPLACE axle shaft.
 
  • Bent axle shaft or housing; axle shafts on different centerlines.
  • REPLACE bent axle shafts or housing or REALIGN hub faces and bolt circles in both the differential carrier and axle housing.
 
  • Incorrect wheel alignment.
  • CORRECT as required.
  • Grinding Noises
  • Improper installation; damaged differential.
  • PERFORM Installation Test.
 
  • Broken axle shaft.
  • REPLACE axle shaft.
 
  • Bent axle or housing; axle shafts on different centerlines.
  • REPLACE bent axle shafts or housing or REALIGN hub faces and bolt circles in both the differential carrier and axle housing.
 
  • Worn or damaged axle components.
  • CHECK the condition of the ring gear, pinion gear, bearings, seals, etc. REPLACE as required.
 
  • Foreign matter in axle housing or improper assembly of axle components.
  • INSPECT for contamination. CHECK assembly of axle components.
 
  • Incorrect ring and pinion adjustments; worn driveline components.
  • REPLACE or ADJUST components as required.
  • Continuous Clicking Sound in Straight Forward Driving
  • Improper installation; damaged differential carrier and axle housing.
  • PERFORM Installation Test.
 
  • Overloading or improper weight distribution.
  • REMOVE excess weight and REDISTRIBUTE the load from side to side according to the vehicle/axle manufacturer's instructions.
 
  • Bent axle shaft or housing; axle shafts on different centerlines.
  • REPLACE bent axle shafts or housing or REALIGN hub faces and bolt circles in both the differential carrier and axle housing.
 
  • Unequal rolling radii of the drive wheel.
  • REPLACE tires or ADJUST tire pressures until rolling radii are equal.
  • Excessive Backlash in Vehicle Drivetrain; Engine Lug or Vehicle Surge During Turns
  • Improper installation; damaged differential.
  • PERFORM Installation Test.
 
  • Worn or damaged axle components.
  • CHECK the condition of the ring gear, pinion gear, bearings, seals, etc. REPLACE as required.
 
  • Incorrect ring and pinion adjustments; worn driveline components.
  • REPLACE or ADJUST components as required.
  • Tendency to Side-Slip or Fishtail on Icy Roads
  • High crown in road; poor traction surface under all drive wheels.
  • DECELERATE when side-slip starts to occur. DO NOT BRAKE.
  • Sluggish Re-engagement of Detroit Locker® Differential Clutch Assemblies
  • Worn or damaged axle components.
  • CHECK the condition of the ring gear, pinion gear, bearings, seals, etc. REPLACE as required.
 
  • High viscosity lubricant.
  • DRAIN and REPLACE with proper lubricant.

    NOTE: The Detroit Locker® differential can operate with any axle lubricant, but weather conditions can adversely affect performance if lubricant is too thick or too thin.
  • Difficulty in Turning Vehicle from Standing Start
  • Improper installation; damaged differential.
  • PERFORM Installation Test.
 
  • Broken axle shaft.
  • REPLACE axle shaft.
 
  • Bent axle shaft or housing; axle shafts on different centerlines.
  • REPLACE bent axle shafts or housing or REALIGN hub faces and bolt circles in both the differential carrier and axle housing.
  • Erratic Operation of Detroit Locker® Differential; Premature Wear or Failure of Detroit Locker® Differential Components
  • Improper installation; damaged differential.
  • PERFORM Installation Test.
 
  • Overloading or improper weight distribution.
  • REMOVE excess weight and REDISTRIBUTE the load from side to side according to the vehicle/axle manufacturer's instructions.
 
  • Unequal rolling radii of the drive wheel.
  • REPLACE tires or ADJUST tire pressures until rolling radii are equal.
 
  • Broken axle shaft.
  • REPLACE axle shaft.
 
  • Bent axle shaft or housing; axle shafts on different centerlines.
  • REPLACE bent axle shafts or housing or REALIGN hub faces and bolt circles in both the differential carrier and axle housing.
 
  • Worn or defective axle components.
  • CHECK the condition of the ring gear, pinion gear, bearings, seals, etc. REPLACE as required.
 
  • Foreign matter in axle housing or improper assembly of axle components.
  • INSPECT for contamination. CHECK assembly of axle components.
 
  • Incorrect ring and pinion adjustments; worn driveline components.
  • REPLACE or ADJUST components as required.
 
  • High viscosity lubricant.
  • DRAIN and REPLACE with proper lubricant.

    NOTE: The Detroit Locker® differential can operate with any axle lubricant, but weather conditions can adversely affect performance if lubricant is too thick or too thin.