2005 Jeep Grand Cherokee Owner Manual - Page 236

236 STARTING AND OPERATING left "D(-)" and hold it there. The transmission will shift to the range from which the vehicle can best be slowed down. Overdrive Operation The overdrive automatic transmission contains an electronically controlled fourth and fifth speed (Overdrive). The transmission will automatically shift from 3rd gear to Overdrive if the following conditions are present: • the transmission selector is in D (Drive); • the engine coolant has reached normal operating temperature; • vehicle speed is above approximately 30 mph (48 km/h); • the "TOW/HAUL" button has not been activated; • transmission has reached normal operating temperature. NOTE: If the vehicle is started in extremely cold temperatures, the transmission may not shift into Overdrive and will automatically select the most desirable gear for operation at this temperature. Normal operation will resume when the transmission fluid temperature has risen to a suitable level. Refer also to the Note under torque converter clutch, later in this section. If the transmission temperature gets extremely hot, the transmission will automatically select the most desirable gear for operation at this temperature. If the transmission temperature becomes hot enough, the "TRANSMISSION OVER TEMP" message may display and the transmission may downshift out of Overdrive until the transmission cools down. After cooldown, the transmission will resume normal operation. In high ambient temperatures with sustained high engine speed and load, an upshift followed shortly thereafter by