Hub lock Engagement/Disengagement Time

WARNING: This page is about a different car, the 2009 Ford Pickup, 2009 Ford F550 Super Duty, 2009 Ford F450 Super Duty, and 2009 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

With the hub lock dials in the AUTO position, switching the instrument panel MSS to 4X4 High or 4X4 Low results in the high vacuum level being applied to the hub locks, which lasts for at least 51 seconds (including a venting cycle). The hub locks should engage during this time through the spring mechanism. Switching the MSS to 2WD less than 51 seconds after the MSS has been switched to 4X4 High or 4X4 Low will not interrupt the high vacuum level; instead, the lower vacuum level will be applied after the high vacuum level cycle is completed.

With the hub lock dials in the AUTO position, switching the MSS to 2WD results in the lower vacuum level being applied to the hub locks, which lasts for about 15 seconds. However, the actual time required for the hub locks to disengage by spring force can vary considerably due to the effects of driveline wind up. Road bumps, vehicle speed, acceleration cycles or momentary reversal of direction can assist this process. Switching the MSS to 4X4 High or 4X4 Low always overrides the lower vacuum level cycle and results in an immediate high-vacuum level and in locking of the hub locks.