Lincoln Aviator: Front Drive Axle/Differential / Diagnosis and Testing - Front Drive Axle

Principles of Operation

Inspection and Verification

  1. Verify the customer concern.
  1. Visually inspect for obvious signs of mechanical or electrical damage.
  1. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
  1. If the cause is not visually evident, verify the symptom and refer to the Symptom Chart.

Symptom Chart - Front Differential

  Symptom Chart - Front Differential


Condition Possible Sources Actions
Axle overheating
  • Axle lubricant low
  • CHECK the lubricant level. FILL the axle to specification.
    REFER to: Specifications (205-03 Front Drive Axle/Differential, Specifications).
  • Incorrect or contaminated lubrication type
  • INSPECT the axle for damage. REPAIR as necessary. DRAIN and REFILL the axle to specification as necessary.
    REFER to: Specifications (205-03 Front Drive Axle/Differential, Specifications).
  • Bearing preload adjusted too tight
  • If low mileage unit, CHECK the ring and pinion for damage. INSTALL new front axle as necessary
    REFER to: Axle Assembly (205-03 Front Drive Axle/Differential, Removal and Installation).
  • Excessive gear wear
  • INSPECT all the axle gears for wear or damaged. INSTALL new front axle as necessary
    REFER to: Axle Assembly (205-03 Front Drive Axle/Differential, Removal and Installation).
Broken gear teeth on the ring gear or pinion
  • Insufficient lubrication
  • INSTALL a front axle assembly.
    REFER to: Axle Assembly (205-03 Front Drive Axle/Differential, Removal and Installation).
Differential side gears / pinion gears are scored
  • Incorrect or contaminated lubricant type
  • Drain and FILL the axle to specification.
    REFER to: Differential Draining and Filling (205-03 Front Drive Axle/Differential, General Procedures).
    Road test vehicle. If an observable symptom is present (noise from front axle), INSTALL new front axle assembly as necessary.REFER to: Axle Assembly (205-03 Front Drive Axle/Differential, Removal and Installation).
Lubricant leaking from the pinion seal, axle shaft oil seals
  • Vent
  • CLEAN the axle housing vent.
  • Damage in the seal contact area or pinion flange dust shield
  • INSTALL a new pinion nut and the pinion seal if damage is found.
    REFER to: Drive Pinion Seal (205-03 Front Drive Axle/Differential, Removal and Installation).
  • Damage in the seal contact area
  • INSTALL a new halfshaft seal as necessary. Inspect Halfshaft seal contact area. Install new halfshaft as necessary.
    REFER to: Axle Shaft Seal (205-03 Front Drive Axle/Differential, Removal and Installation).
Grease expelling from pinion splines
  • Missing / worn / damaged driveshaft to pinion circlip
  • Missing / Damaged front axle pinion stem O-Ring
  • REMOVE the Front Driveshaft. INSTALL New Circlip and O-Ring. INSTALL the new Front Driveshaft as necessary.
    REFER to: Front Driveshaft (205-01 Driveshaft, Removal and Installation).

Symptom Chart - NVH

NOTE: NVH symptoms should be identified using the diagnostic tools that are available. For a list of these tools, an explanation of their uses and a glossary of common terms, refer to Section 100-04. Since it is possible any one of multiple systems may be the cause of a symptom, it may be necessary to use a process of elimination type of diagnostic approach to pinpoint the responsible system.


REFER to: Noise, Vibration and Harshness (NVH) (100-04 Noise, Vibration and Harshness, Diagnosis and Testing).


  Symptom Chart - NVH


Condition Possible Sources Actions
NVH concern isolated to front axle using proper diagnostic tools. Symptom may be constant or only occurs under specific driving conditions
  • Axle lubricant low or contamination
  • CHECK the lubricant level. FILL the axle to specification.
    REFER to: Differential Fluid Level Check (205-03 Front Drive Axle/Differential, General Procedures).
    OR INSPECT front axle fluid, if required, Drain and FILL the axle to specification. REFER to: Differential Draining and Filling (205-03 Front Drive Axle/Differential, General Procedures).
  • Internal FDU (Front Drive Unit) damage
  • Remove side cover and inspect components for wear or damage. INSTALL a new FDU (Front Drive Unit) as necessary.
    REFER to: Axle Assembly (205-03 Front Drive Axle/Differential, Removal and Installation).
Driveline clunk - loud clunk when shifting from REVERSE to DRIVE
  • Loose or missing fasteners
  • CHECK all driveline fasteners for proper torque.
Driveline clunk — occurs as the vehicle starts to move forward following a stop
  • Loose front axle mount
  • CHECK the front axle for loose bolts. TIGHTEN to proper torque.
    REFER to: Axle Assembly (205-03 Front Drive Axle/Differential, Removal and Installation).
Driveline clunk — occurs during acceleration or from cruise to coast / deceleration
  • Rear driveshaft U-joint
  • Missing or damaged circlip on front axle pinion.
  • INSPECT the rear driveshaft U-joints for wear or damage. INSTALL a new rear driveshaft as necessary.
    REFER to: Rear Driveshaft (205-01 Driveshaft, Removal and Installation).
  • Install new circlip.
Grunting — normally associated with a shudder experienced during acceleration from a complete stop
  • Rear Driveshaft
  • INSPECT the rear Driveshaft. INSTALL the new rear Driveshaft.
    REFER to: Rear Driveshaft (205-01 Driveshaft, Removal and Installation).
Scraping noise — a continuous low pitched noise starting at low speeds
  • Intermediate shaft LH halfshaft seal deflector bent / damaged
  • INSPECT components for wear/damage. INSTALL a new LH Halfshaft seal as necessary.
    REFER to: Axle Shaft Seal (205-03 Front Drive Axle/Differential, Removal and Installation).
Driveline shudder – occurs during acceleration from a slow speed or stop
  • Rear driveshaft
  • INSPECT the rear Driveshaft. INSTALL the new rear Driveshaft.
    REFER to: Rear Driveshaft (205-01 Driveshaft, Removal and Installation).

Axle Fluid Analysis

The appearance of milky fluid could be caused by fluid contamination. Drain and refill fluid and retest for normal operation.
REFER to: Differential Draining and Filling (205-03 Front Drive Axle/Differential, General Procedures).

Analysis of Leakage

Clean up the leaking area enough to identify the exact source.

Axle Vent

A plugged vent will cause excessive seal lip wear due to internal pressure buildup. If a leak occurs, check the vent. If the vent cannot be cleared, install a new vent.

Drive Pinion Seal

Leaks at the drive pinion seal originate from the following causes:

  • Damaged seal
  • Worn seal surface on Pinion Nut

The service kit available comes with seal, nut, & deflector.

Differential Seals

NOTICE: When installing shafts, do not allow splines to contact seals during installation or damage to the seals may occur.

The front axle fluid level is above halfshaft. Top-off the fluid level after replacing either differential seal. The seals are one time use and should be replaced whenever the RH halfshaft or intermediate shaft is removed.

RH halfshaft seal is a typical unitized seal found on many applications. The LH differential seal is the intermediate shaft to oil pan O-Ring.

The intermediate shaft also contains a differential seal to prevent gear lubricant from entering the intermediate shaft. This seal is serviced with the intermediate shaft.

    Description and Operation - Front Drive Axle and Differential

    The 6.5-inch ring gear rear differential axle has 3.31, 3.58 and 3.73 gear ratio versions. Front Drive Axle and Differential The front drive axle consists of: A cast-aluminum center section, a removable cast-aluminum differential housing cover Integral-type housing hypoid gear design (center of the pinion set below the centerline of the ring gear)...

    General Procedures - Differential Draining and Filling

    Materials Name Specification Motorcraft® SAE 75W-140 Synthetic Rear Axle LubricantXY-75W140-QL WSL-M2C192-A  Draining With the vehicle in NEUTRAL, position it on a hoist...

    Other information:

    Lincoln Aviator 2020-2021 Service Manual: Description and Operation - Transmission Description


    Transmission Assembly Item Part Number Description 1 79027902 Torque converter 2 W714629W714629 Transmission fluid pan stud bolts (6 required) 3 W500215W500215 Transmission fluid pan bolts (12 required) 4 7A1947A194 Transmission fluid pan 5 7A1917A191 Transmission fluid pan gasket 6 7E3897E389 Transmission fluid level indicator and plug assembly 7 W708500W708500 Transmission fluid auxiliary pump tube bolt (model dependent) 8 7A2097A209 Transmission fluid auxiliary pump tube (model dependent) 9 W718548W718548 Transmission fluid auxiliary pump bolts (3 required) (model dependent) 10 7P0867P086 Transmission fluid auxiliary pump (model dependent) 11 7J1357J135 Transmission fluid auxiliary pump tube seal (model dependent) 12 W700123W700123 Transmission fluid filter bolt (71 mm length) 13 W500214W500214 Transmission fluid filter bolt (20 mm length) 14 7G1867G186 Transmission fluid filter 15 W708500W708500 Main control-to-transmission case bolts (68 mm length) (8 required) 16 7A1007A100 Main control assembly 17 7N2657N265 Main control-to-transmission fluid pump seal 18 7M1837M183 Intermediate Speed A (ISSA) sensor 19 7M1017M101 Turbine Shaft Speed (TSS) sensor 20 7H1037H103 Intermediate Speed B (ISSB) sensor 21 7H1037H103 Output Shaft Speed (OSS) sensor 22 W500213W500213 Transmission internal wiring harness bolts (2 required) 23 7G2767G276 Transmission internal wiring harness 24 W500215W500215 Transmission fluid pump bolts (4 required) 25 7A1037A103 Transmission fluid pump 26 7Z3027Z302 Transmission fluid pump seal 27 66586658 Transmission fluid pump driven gear outer cover 28 W718158W718158 Transmission fluid pump retaining ring 29 7A0807A080 Transmission fluid pump driven gear 30 W504755W504755 Transmission fluid pump driven gear inner cover bolts (2 required) 31 66586658 Transmission fluid pump driven gear inner cover 32 7K4407K440 Output shaft flange nut (RWD only) 33 7A0217A021 Output shaft flange (RWD only) 34 7N1357N135 Anti-ting washer (RWD only) 35 7G1007G100 Manual control shaft-to-Transmission Range (TR) sensor roll pin 36 W712713W712713-S442-S442 Park override lever nut 37 7J1677J167 Park override lever 38 7C4937C493 Manual control shaft 39 7H5577H557 Transmission Range (TR) sensor 40 7L2527L252 Park return spring 41 7D4107D410 Park pawl actuator rod 42 W716607W716607 Transmission Range (TR) sensor detent spring bolt 43 7E3327E332 Transmission Range (TR) sensor detent spring 44 7N1347N134 Front support assembly bolts (12 required) 45 7G0337G033 Front support assembly 46 7M1577M157-C-C B clutch (overdrive) snap ring 47 7C5767C576 B clutch (overdrive) pressure plate 48 7B4427B442-A-A B clutch (overdrive) steel plates (quantity model dependent) 49 7B1647B164 B clutch (overdrive) friction plates (quantity model dependent) 50 7J4027J402 B clutch (overdrive) separating springs (quantity model dependent) 51 7B4427B442-B-B B clutch (overdrive) apply plate 52 7G2067G206 One-Way Clutch (OWC) 53 7G4187G418 B clutch (overdrive) piston 54 7N1697N169 A clutch (intermediate) piston return spring snap ring 55 7G2977G297 A clutch (intermediate) piston return spring 56 7J0157J015 A clutch (intermediate) piston 57 7F2257F225 A clutch (intermediate) piston inner seal 58 7F2247F224 A clutch (intermediate) piston outer seal 59 7B0317B031 Front support-to-case seal 60 7M1577M157-J-J Torque converter hub seal snap ring 61 7A2487A248 Torque converter hub seal 62 W500204W500204 Front support cover and seal assembly bolt 63 7M1577M157 Front support cover and seal assembly snap ring 64 75707570 Front support cover and seal assembly 65 7F0737F073 Transmission fluid pump drive gear 66 66516651 Transmission fluid pump idler gear 67 7Z4267Z426 Transmission fluid pump idler gear bearing 68 7G0907G090 Stator support seal 69 — Clutch and planetary assembly 70 7P0807P080 A clutch (intermediate) wave spring 71 7A4067A406 A clutch (intermediate) apply plate (select fit) 72 7F2197F219 A clutch (intermediate) friction plates (quantity model dependent) 73 7F2207F220 A clutch (intermediate) steel plates (quantity model dependent) 74 7G1597G159 A clutch (intermediate) separating springs (quantity model dependent) 75 7B4377B437 A clutch (intermediate) pressure plate 76 7J3007J300 Selective shim 77 7H0327H032 Thrust bearing (T3) 78 7M1527M152-A-A Thrust bearing (T9) 79 7A0497A049 Output shaft and planetary carrier No...

    Lincoln Aviator 2020-2021 Service Manual: Removal and Installation - High-Pressure Fuel Pump


    Removal NOTICE: Do not loosen any fittings or plugs on the high-pressure fuel pump. With the vehicle in NEUTRAL, position it on a hoist. Refer to: Jacking and Lifting (100-02 Jacking and Lifting, Description and Operation). Release the fuel system pressure...

    Categories

    Child Safety Locks

    When the child safety locks are set, you cannot open the rear doors from the inside.

    Lincoln Aviator. Child Safety Locks

    The child safety lock control is on the driver door.

    Press the control to switch the child safety locks on. Press the control again to switch them off. A light on the child safety control illuminates when you switch them on.

    read more

     
    Copyright © 2021 www.liaviator2.com