Pinpoint Test F: Mechanical Shift On Stop (MSOS) Functional Test

Pinpoint Test F: Mechanical Shift On Stop (MSOS) Functional Test

Normal Operation

When operating in 4H mode, the transfer case locks the front driveline to the rear. When set to the locked position, the manual hublocks connect the front axleshafts to the wheel hubs. When in 4L mode, the transfer case low range gear set provides an additional 2.72:1 gear reduction. When operating in 2H mode, the transfer case decouples the front driveline from the rear driveline. For improved fuel economy both manual hublocks should be set to "Free" in 2H mode.

Possible Causes
- Transfer case and related components
- Wheel and tire assemblies
- Front axle assembly
- MSOS mode indication switch (MIS)
- Circuitry

NOTE: 4X4 high/low (4H/4L) is not intended for driving on hard/dry surfaces.