2009 Dodge Durango Owner Manual - Page 320

318 STARTING AND OPERATING NOTE: To improve the vehicle's traction when driving with snow chains, or starting off in deep snow, sand or gravel, it may be desirable to switch to the "Partial Off" mode by pressing the ESP OFF switch. Once the situation requiring ESP to be switched to the "Partial Off" mode is overcome, turn ESP on by momentarily depressing the ESP OFF switch. This may be done with the vehicle in motion. 4WD LOW Range Partial Off This is the normal operating mode for ESP in 4WD LOW. Whenever the vehicle is started in 4WD LOW or the transfer case (if equipped) is shifted from 4WD LOCK or NEUTRAL to 4WD LOW, the ESP system will be in this mode. In 4WD LOW, ESP function is desensitized until the vehicle reaches a speed of 30 mph (48 km/h). At 30 mph (48 km/h) the normal ESP stability function returns and the ESP/TCS Indicator Light turns off. When the vehicle speed drops below 25 mph (40 km/h) the ESP system goes back to "Partial Off." ESP is desensitized at low vehicle speeds in 4WD LOW so that it will not interfere with off road driving but ESP function returns to provide the stability feature at speeds above 30 mph (48 km/h). The ABS is in a special Off Road mode that allows wheels to lock at lower speeds if gravel is detected to shorten stopping distances. NOTE: When the vehicle is in 4WD LOW, a feature of the ESP system remains active whether the ESP is on or off. This feature functions similar to a limited slip differential and controls the wheel spin across an axle. If one wheel on an axle is spinning faster than the other, the system will apply the brake of the spinning wheel and allow more engine torque to be applied to the wheel that is not spinning.