2005 Jeep Wrangler Owner's Manual - Page 188
2005 Jeep Wrangler Manual
Page 188 highlights
188 STARTING AND OPERATING When frequent transmission shifting occurs while using Overdrive, such as when operating the vehicle under heavy load conditions (for example, in hilly terrain, strong head winds, or trailer towing), turning off overdrive will improve performance and extend transmission life by reducing excessive shifting and heat buildup. Overdrive can be locked out by pressing the O/D OFF switch located on the instrument panel. The O/D OFF indicator light (on the switch) will illuminate to show that the switch has been activated. When the indicator light is on, Overdrive is locked out. Pressing the switch a second time restores the Overdrive function. The lockout feature is useful when towing a trailer or carrying a heavy load. 2 (Second) For moderate grades and to assist braking on dry pavement or in mud and snow. Begins at a stop in low gear with automatic upshift to 2nd gear. Will not shift to 3rd. 1 (First) For hard pulling at low speeds in mud, sand, snow, or on steep grades. Begins and stays in low gear with no upshift. Provides engine compression braking at low speeds. Overdrive Off Switch