On older Navigators the ControlTrac 4-wheel-drive system is virtually the same as the Expedition.
However, the 2007 model year saw the departing of the Navigator from the Expedition’s 4-wheel-drive system.
The Expedition still has a proper 4-wheel-drive system with a center differential that can be locked in high or low range gearing. 4A and 4H modes can be shifted on the move (below a certain speed) from 2H mode. To access 4L mode, the Expedition must be brought to a halt and the 6-seed automatic transmission shifted into neutral. Only then can you bump the dial to 4L. "4x4 Shift In Progress" will display in the message center, then the appropriate mode will display letting you know the shift was successful and what mode your in.
To access the Expedition’s off road crawl, make sure 4L mode is selected, this locks the center differential and engages 2.64:1 low range gearing. Simply shift the 6-speed automatic transmission into manual 1st gear. If the Expedition has the optional 3.73:1 rear axle ratio (code 16), the off road crawl ratio will be 41.06:1.
For 2007-2008 Expedition AdvanceTrac operation:
To disable engine management, electronic stability control (ESC) and roll stability control (RSC) for off road use, simply depress the AdvanceTrac deactivation button (sliding car icon) on the dash. 4-wheel electronic traction control will continue to function. Engine management, ESC and RSC will stay deactivated, but will reactivate if the vehicle goes over 25 mph. The system is designed for traditional low speed off roading. ESC and RSC are automatically disabled when 4L mode is selected.
2009 Expeditions do not disable ESC and RSC in 4L mode. Engine management, electronic stability control (ESC) and roll stability control (RSC) can still be deactivated by depressing the AdvanceTrac deactivation button. Again the systems will stay off below 25 mph.
2010 Expeditions will only disable engine management, ESC and RSC in 4L mode.
2007-onward Navigators do not have low range gearing, but can disable engine management, ESC and RSC like the Expedition up to the 2009 model year.
2010 Navigators cannot disable engine management, ESC or RSC. These systems are always-on.