4x4 Vans : Quigley Motor Company, Inc. > Technical Center > Ford Transit Tech Center > Operation Instructions

Operating Instructions

Instructions for IFS 4x4 System

The Quigley Transit 4x4 Independent Front Suspension (IFS) vehicles utilize front automatic locking hubs. This 4x4 system is devoid of either manual lock-out hubs. Instead, the differential engages the front axle halves into the 4-wheel drive application when the vehicle's transfer case is shifted via vacuum. The locking mechanism for the hub is free by use of vacuum.  When the vacuum is lost the hub locks onto the axle shafts.

CAUTION: When transfer case is in "N" (neutral), the transmission "PARK" feature is disabled. Parking brake must be applied or vehicle may move unexpectedly, causing serious injury or death.

Best Practices: Shift into 4WD only when conditions require traction. When the need for a 4-wheel drive is no longer anticipated shift transfer case back into the 2H position. 

The Quigley IFS 4x4 system can be shifted from 2-wheel-high (2H) to 4-wheel-high (4H) or from 4H to 2H while the vehicle is in motion up to speeds of 55 mph. However, you may not shift into 4H while accelerating. In extremely cold weather, it may be necessary to stop or slow the vehicle to shift into 4H.

To shift into or out of 4-wheel-low (4L) slow vehicle to a crawl (1 – 3 mph) and shift the transfer case lever in one continuous motion to 4L. DO NOT PAUSE in the NEUTRAL (N) position as you shift the transfer case or your gears could clash. If clashing of gears occur then turn off the engine and proceed to shift into 4L.