Lincoln Navigator Manuals

Lincoln Navigator: Driveshaft / Driveshaft. Diagnosis and Testing

Lincoln Navigator 2018-2025 Workshop Manual / Driveline / Driveshaft / Driveshaft. Diagnosis and Testing

Symptom Chart(s)

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices.
REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).

Symptom Chart: NVH

  Symptom Chart


Condition Actions
Driveline clunk - loud clunk when shifting from REVERSE to DRIVE   GO to Pinpoint Test A
Driveline clunk — occurs as the vehicle starts to move forward following a stop   GO to Pinpoint Test B
Driveline Clunk– Fastener Torque to transmission and rear axle   GO to Pinpoint Test C
Buzz – buzzing noise is the same at cruise or coast/deceleration   GO to Pinpoint Test D
Rumble or Boom – noise occurs at coast/ deceleration, usually driveshaft speed-related and noticeable over a wide range of speeds   GO to Pinpoint Test E
Grunting — normally associated with a shudder experienced during acceleration from a complete stop   GO to Pinpoint Test F
Driveline shudder – occurs during acceleration from a slow speed or stop   GO to Pinpoint Test G
Driveline vibration - occurs at cruising speeds   GO to Pinpoint Test H

Global Customer Symptom Code (GCSC) Chart

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices.
REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).


Symptom Action
Start/Run/Move > Noise > Moving/Driving > Always GO to Pinpoint Test A
Start/Run/Move > Noise > Moving/Driving > Always GO to Pinpoint Test B
Start/Run/Move > Noise > Moving/Driving > Always GO to Pinpoint Test C
Start/Run/Move > Noise > Moving/Driving > Always GO to Pinpoint Test D
Start/Run/Move > Noise > Moving/Driving > Always GO to Pinpoint Test E
Start/Run/Move > Noise > Moving/Driving > Always GO to Pinpoint Test F
Start/Run/Move > Vibration > Moving/Driving > Intermittent GO to Pinpoint Test G
Start/Run/Move > Vibration > Moving/Driving > Intermittent GO to Pinpoint Test H

Pinpoint Tests


PINPOINT TEST A: DRIVELINE CLUNK- LOUD CLUNK WHEN SHIFTING FROM REVERSE TO DRIVE

Normal Operation and Fault Conditions

The driveline system enables the power generated by the engine and transferred through the transmission and, if applicable, transfer case, to place the vehicle in motion. Rotational torque received from the transmission or transfer case is delivered to the front and rear drive axles by way of the driveshafts. The U-joints or CV joints at the ends of the shafts allow the shafts to rotate smoothly in an allowable angle plane. The rotational torque is introduced into the axle differential which drives the axles/halfshaft.

Possible Sources

  • Damaged or worn driveshaft U-joint
A1 INSPECT THE DRIVESHAFT U-JOINTS FOR WEAR OR DAMAGE
  • Inspect the driveshaft U-joints for wear or damage.

Was any damage found?
Yes Install a new U-joint or driveshaft as necessary.
REFER to: Driveshaft Universal Joint (205-01 Driveshaft, Disassembly and Assembly).
No Inspect the vehicle for any other symptoms related to the driveshaft.

PINPOINT TEST B: DRIVELINE CLUNK- OCCURS AS THE VEHICLE STARTS TO MOVE FORWARD FOLLOWING A STOP

Normal Operation and Fault Conditions

The driveline system enables the power generated by the engine and transferred through the transmission and, if applicable, transfer case, to place the vehicle in motion. Rotational torque received from the transmission or transfer case is delivered to the front and rear drive axles by way of the driveshafts. The U-joints or CV joints at the ends of the shafts allow the shafts to rotate smoothly in an allowable angle plane. The rotational torque is introduced into the axle differential which drives the axles/halfshaft.

Possible Sources

  • Worn driveshaft U-joint with excessive play
B1 INSPECT THE DRIVESHAFT U-JOINT FOR A WORN CONDITION
  • Inspect the driveshaft U-joint for a worn condition.

Was any damage found?
Yes Install a new driveshaft U-joint as necessary.
REFER to: Driveshaft Universal Joint (205-01 Driveshaft, Disassembly and Assembly).
No Inspect the vehicle for any other symptoms related to the driveshaft.

PINPOINT TEST C: DRIVELINE CLUNK– FASTENER TORQUE TO TRANSMISSION AND REAR AXLE

Normal Operation and Fault Conditions

The driveline system enables the power generated by the engine and transferred through the transmission and, if applicable, transfer case, to place the vehicle in motion. Rotational torque received from the transmission or transfer case is delivered to the front and rear drive axles by way of the driveshafts. The U-joints or CV joints at the ends of the shafts allow the shafts to rotate smoothly in an allowable angle plane. The rotational torque is introduced into the axle differential which drives the axles/halfshaft.

Possible Sources

  • Loose or crossthreaded fasteners
C1 CHECK FOR LOOSE OR CROSSTHREADED FASTENERS
  • Check for loose or crossthreaded fasteners.

Are any fasteners loose?
Yes Install new fasteners or install a new driveshaft U-joint or driveshaft as necessary.
REFER to: Driveshaft Universal Joint (205-01 Driveshaft, Disassembly and Assembly).
REFER to: Rear Driveshaft (205-01 Driveshaft, Removal and Installation).
No Inspect the vehicle for any other symptoms related to the driveshaft.

PINPOINT TEST D: BUZZ – BUZZING NOISE IS THE SAME AT CRUISE OR COAST/DECELERATION

Normal Operation and Fault Conditions

The driveline system enables the power generated by the engine and transferred through the transmission and, if applicable, transfer case, to place the vehicle in motion. Rotational torque received from the transmission or transfer case is delivered to the front and rear drive axles by way of the driveshafts. The U-joints or CV joints at the ends of the shafts allow the shafts to rotate smoothly in an allowable angle plane. The rotational torque is introduced into the axle differential which drives the axles/halfshaft.

Possible Sources

  • Incorrect driveline angles
D1 CHECK DRIVELINE ANGLES
  • Check driveline angles.

Are the driveline angles incorrect?
Yes Repair as necessary.
REFER to: Driveshaft Angle Measurement (205-01 Driveshaft, General Procedures).
No Inspect the vehicle for any other symptoms related to the driveshaft.

PINPOINT TEST E: RUMBLE OR BOOM – NOISE OCCURS AT COAST/ DECELERATION, USUALLY DRIVESHAFT SPEED-RELATED AND NOTICEABLE OVER A WIDE RANGE OF SPEEDS

Normal Operation and Fault Conditions

The driveline system enables the power generated by the engine and transferred through the transmission and, if applicable, transfer case, to place the vehicle in motion. Rotational torque received from the transmission or transfer case is delivered to the front and rear drive axles by way of the driveshafts. The U-joints or CV joints at the ends of the shafts allow the shafts to rotate smoothly in an allowable angle plane. The rotational torque is introduced into the axle differential which drives the axles/halfshaft.

Possible Sources

  • Driveshaft out of balance
E1 CHECK THE DRIVESHAFT FOR DAMAGE, MISSING WEIGHTS OR UNDERCOATING
  • Check the driveshaft for damage, missing weights or undercoating.

Was the driveshaft damaged or out of balance?
Yes Repair as necessary.
REFER to: Rear Driveshaft (205-01 Driveshaft, Removal and Installation).
REFER to: Driveshaft Runout and Balancing (205-01 Driveshaft, General Procedures).
No Inspect the vehicle for any other symptoms related to the driveshaft.

PINPOINT TEST F: GRUNTING- NORMALLY ASSOCIATED WITH A SHUDDER EXPERIENCED DURING ACCELERATION FROM A COMPLETE STOP

Normal Operation and Fault Conditions

The driveline system enables the power generated by the engine and transferred through the transmission and, if applicable, transfer case, to place the vehicle in motion. Rotational torque received from the transmission or transfer case is delivered to the front and rear drive axles by way of the driveshafts. The U-joints or CV joints at the ends of the shafts allow the shafts to rotate smoothly in an allowable angle plane. The rotational torque is introduced into the axle differential which drives the axles/halfshaft.

Possible Sources

  • Driveshaft CV joint and/or U-joint binding
F1 INSPECT THE DRIVESHAFT CV (CONSTANT VELOCITY) JOINT AND/OR U-JOINT FOR A BINDING
  • Inspect the driveshaft CV joint and/or U-joint for a binding.

Was the driveshaft CV joint binding found ?
Yes Install a new driveshaft as necessary.
REFER to: Rear Driveshaft (205-01 Driveshaft, Removal and Installation).
REFER to: Front Driveshaft (205-01 Driveshaft, Removal and Installation).
No Inspect the vehicle for any other symptoms related to the driveshaft.

PINPOINT TEST G: DRIVELINE SHUDDER- OCCURS DURING ACCELERATION FROM A SLOW SPEED OR STOP

Normal Operation and Fault Conditions

The driveline system enables the power generated by the engine and transferred through the transmission and, if applicable, transfer case, to place the vehicle in motion. Rotational torque received from the transmission or transfer case is delivered to the front and rear drive axles by way of the driveshafts. The U-joints or CV joints at the ends of the shafts allow the shafts to rotate smoothly in an allowable angle plane. The rotational torque is introduced into the axle differential which drives the axles/halfshaft.

Possible Sources

  • Driveline angles out of specification
  • Binding or damaged driveshaft CVCV joint and/or U-joint
G1 CHECK DRIVELINE ANGLES
  • Check driveline angles.

Are the driveline angles incorrect?
Yes Repair as necessary.
REFER to: Driveshaft Angle Measurement (205-01 Driveshaft, General Procedures).
No Inspect the vehicle for any other symptoms related to the driveshaft.

G2 INSPECT THE DRIVESHAFT CV (CONSTANT VELOCITY) JOINTS AND/OR U-JOINT AND COUPLING SHAFT FOR WEAR OR DAMAGE
  • Inspect the driveshaft CV joints and/or U-joint and coupling shaft for wear or damage.

Was wear or damage found?
Yes Install a new driveshaft as necessary.
REFER to: Rear Driveshaft (205-01 Driveshaft, Removal and Installation).
REFER to: Front Driveshaft (205-01 Driveshaft, Removal and Installation).
No Inspect the vehicle for any other symptoms related to the driveshaft.

PINPOINT TEST H: DRIVELINE VIBRATION - OCCURS AT CRUISING SPEEDS

Normal Operation and Fault Conditions

The driveline system enables the power generated by the engine and transferred through the transmission and, if applicable, transfer case, to place the vehicle in motion. Rotational torque received from the transmission or transfer case is delivered to the front and rear drive axles by way of the driveshafts. The U-joints or CV joints at the ends of the shafts allow the shafts to rotate smoothly in an allowable angle plane. The rotational torque is introduced into the axle differential which drives the axles/halfshaft.

Possible Sources

  • Worn or damaged driveshaft center bearing support
  • Center bearing bolts not seated properly
  • Loose axle pinion flange bolts
  • Excessive axle pinion flange runout
  • Driveshaft is out of balance
  • Binding or damaged driveshaft CV joint and/or U-joint
  • Excessive driveshaft runout
  • Driveline angles out of specification
H1 CHECK THE DRIVESHAFT CENTER BEARING INSULATOR FOR DAMAGE OR WEAR
  • Check the driveshaft center bearing insulator for damage or wear.
  • Rotate the driveshaft and check for rough operation.

Was wear or damage found?
Yes Install a new driveshaft as necessary.
REFER to: Rear Driveshaft (205-01 Driveshaft, Removal and Installation).
No GO to H2

H2 CHECK FOR CENTER BEARING BOLTS NOT SEATED PROPERLY
  • Check for center bearing bolts not seated properly.

Are the center bearing bolts not seated properly?
Yes Tighten to specifications.
REFER to: Rear Driveshaft (205-01 Driveshaft, Removal and Installation).
No GO to H3

H3 CHECK FOR LOOSE AXLE PINION FLANGE BOLTS
  • Check for loose axle pinion flange bolts.

Are any bolts loose?
Yes Tighten to specifications.
REFER to: Rear Driveshaft (205-01 Driveshaft, Removal and Installation).
No GO to H4

H4 CHECK FOR AXLE PINION FLANGE RUNOUT
  • Check for axle pinion flange runout.

Are the runout correct?
Yes Inspect the vehicle for any other symptoms related to the driveshaft.
No Carry out a runout check and repair as necessary.
REFER to: Driveshaft Runout and Balancing (205-01 Driveshaft, General Procedures).

H5 CHECK THE DRIVESHAFT FOR DAMAGE, MISSING WEIGHTS OR UNDERCOATING
  • Check the driveshaft for damage, missing weights or undercoating.
  • Check the driveshaft balance.

Was a system fault found ?
Yes
REFER to: Driveshaft Runout and Balancing (205-01 Driveshaft, General Procedures).
No GO to H6

H6 INSPECT THE DRIVESHAFT CV (CONSTANT VELOCITY) JOINTS AND/OR U-JOINT FOR WEAR OR DAMAGE
  • Inspect the driveshaft CV joints and/or U-joint for wear or damage.

Was wear or damage found?
Yes Install a new driveshaft as necessary.
REFER to: Rear Driveshaft (205-01 Driveshaft, Removal and Installation).
REFER to: Front Driveshaft (205-01 Driveshaft, Removal and Installation).
No GO to H7

H7 CHECK FOR DRIVESHAFT RUNOUT
  • Check for driveshaft runout.

Are the runout correct?
Yes Inspect the vehicle for any other symptoms related to the driveshaft.
No Carry out a runout check.
REFER to: Driveshaft Runout and Balancing (205-01 Driveshaft, General Procedures).

H8 CHECK DRIVELINE ANGLES
  • Check driveline angles.

Are the driveline angles incorrect?
Yes Repair as necessary.
REFER to: Driveshaft Angle Measurement (205-01 Driveshaft, General Procedures).
No Inspect the vehicle for any other symptoms related to the driveshaft.


    Specifications

    ..

    Driveshaft Angle Measurement. General Procedures

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    Diagnostic Methods. Description and Operation

    This document provides critical diagnostic knowledge required for successful repair outcomes. It identifies technical competencies expected by users of this manual.

    Ford Diagnostic Assumptions

    Ford diagnostics assume the vehicle concern described by the test title is currently present. Exceptions to this rule are noted in each test. Do not replace modules or other components as directed by a diagnostic if the concern is not present at the time of testing.

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