LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Ford >> 2023 >> Explorer Timberline >> Repair and Diagnosis >> External Pages >> Different car >> Section 182 (Four-Wheel Drive Systems) >> Diagnosis And Testing >> Four-Wheel Drive Systems - Mechanical Shift >> Pinpoint Tests >> Pinpoint Test F : Manual Shift-On-Stop (MSOS) Functional Test >> Pinpoint Test F : MSOS Functional Test
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Pinpoint Test F : MSOS Functional Test

WARNING: This page is about a different car, the 2019 Ford F-550 Super Duty, 2019 Ford F-450 Super Duty, 2019 Ford F-350 Super Duty, and 2019 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Vehicles equipped with the Manual Shift-On-Stop (MSOS) system and manual hublocks should not be operated in 4H or 4L mode with the hublocks set to the FREE position. Doing so can result in damage to driveline components.
NOTE: 4H (4X4 HIGH) and 4L (4X4 LOW) are not intended for driving on hard/dry surfaces.

  1. F1 CHECK FOR 2H INDICATION

    • Ignition ON.

    • Shift the transfer case shift lever to 2H.

    • Observe the IPC 4x4 High and 4x4 Low indicators.

    Are both indicators off? 

    Yes  GO to  F2
    No  GO to Pinpoint Test A 

  2. F2 CHECK THE MANUAL HUBLOCK OPERATION

    • Turn the LH and RH hublocks to the LOCK position.

    Do the hublocks turn to the LOCK position? 

    Yes  GO to  F3
    No  INSTALL a new manual hublock as necessary.

  3. F3 CHECK FOR MECHANICAL ENGAGEMENT IN 2H

    • Drive the vehicle in tight turns on a hard surface.

    • Check for the presence of driveline wind up and tire scuff.

    Is driveline wind up and tire scuff present? 

    Yes  GO to Pinpoint Test B 
    No  GO to  F4

  4. F4 VERIFY THE SHIFT TO 4H

    • Shift the transfer case shift lever to 4H.

    Did the transfer case shift lever shift to the 4H position? 

    Yes  GO to  F6
    No  GO to  F5

  5. F5 ATTEMPT TO MECHANICALLY ASSIST 4H SHIFT

    • While rolling at speed below 5 km/h (3 mph), shift the transmission to NEUTRAL.

    • Shift the transfer case shift lever to the 4H position while the vehicle is rolling at a speed below 5 km/h (3 mph).

    Did the transfer case shift lever shift to the 4H position? 

    Yes  GO to  F6
    No  GO to Pinpoint Test B 

  6. F6 CHECK MECHANICAL ENGAGEMENT OF 4H

    • Drive the vehicle in tight turns on a hard surface.

    • Check for the presence of driveline wind up and tire scuff.

    Is driveline wind up and tire scuff present? 

    Yes  GO to  F7
    No  GO to Pinpoint Test B 

  7. F7 CHECK THE 4X4 INDICATOR

    • With the transfer case in 4H, observe the IPC 4X4 indicator.

    Does the 4X4 HIGH indicator illuminate? 

    Yes  GO to  F8
    No  GO to Pinpoint Test A 

  8. F8 VERIFY THE SHIFT TO 4L

    • With the vehicle stationary, shift the transmission to NEUTRAL.

    • Shift the transfer case shift lever to 4L.

    Did the transfer case shift lever shift to 4L? 

    Yes  GO to  F10
    No  GO to  F9

  9. F9 ATTEMPT TO MECHANICALLY ASSIST A SHIFT TO 4L

    • While rolling at speed below 5 km/h (3 mph), shift the transmission to NEUTRAL.

    • Shift the transfer case shift lever to the 4L position while the vehicle is rolling at a speed below 5 km/h (3 mph).

    Did the transfer case shift lever shift to the 4L position? 

    Yes  GO to  F12
    No  GO to Pinpoint Test C 

  10. F10 CHECK FOR MECHANICAL ENGAGEMENT OF 4L

    • Execute tight turns on a hard surface.

    • Check for the presence of driveline wind up, tire scuff and limited vehicle speed.

    Is driveline wind up and tire scuff present? 

    Yes  GO to  F11
    No  GO to Pinpoint Test C 

  11. F11 CHECK THE 4X4 LOW RANGE INDICATOR

    • Observe the 4X4 low indicator.

    Is the 4X4 low indicator illuminated? 

    Yes  GO to  F12
    No  GO to Pinpoint Test A 

  12. F12 CHECK THE SHIFT FROM 4L TO 2H

    • With the vehicle stationary, shift the transmission to NEUTRAL.

    • Shift the transfer case shift lever to the 2H position.

    Did the transfer case shift lever shift to the 2H position? 

    Yes  GO to  F14
    No  GO to  F13

  13. F13 ATTEMPT TO MECHANICALLY ASSIST 4L DISENGAGEMENT

    • Allow the vehicle to roll forward to eliminate shift blockage or driveline wind-up.

    • While rolling, shift the transmission to NEUTRAL.

    • Shift the transfer case shift lever to the 2H position at a vehicle speed below 5 km/h (3 mph).

    Did the transfer case shift lever shift to the 2H position? 

    Yes  GO to  F14
    No  GO to Pinpoint Test C 

  14. F14 CHECK THE MANUAL HUBLOCKS RETURN TO FREE

    • Turn the LH and RH manual hublocks to FREE.

    Will the hublocks turn to the FREE position? 

    Yes  GO to  F15
    No  INSTALL a new manual hublock. REFER to: Hublock .

  15. F15 VERIFY THAT THE HUBLOCKS DISENGAGE IN THE FREE POSITION

    • Lift and support the vehicle so that the front tires are a few inches off the ground. Refer to Jacking And Lifting .

    • Rotate the LH front tire while observing the LH front axle shaft and U-joint.

    • Rotate the RH front tire while observing the RH front axle shaft and U-joint.

    Does either axle shaft rotate? 

    Yes  INSTALL a new manual hublock. REFER to: Hublock .
    No  GO to  F16

  16. F16 VERIFY THAT THE TRANSFER CASE DISENGAGED MECHANICALLY

    • Apply the parking brake.

    • Rotate the front driveshaft.

    Does the front driveshaft rotate? 

    Yes  The 4WD system is operating correctly.
    No  REPAIR the transfer case as necessary. REFER to: Transfer Case .
scientia non olet · About LEMON Manuals