2000 GMC Sierra 1500 Pickup Owner's Manual - Page 157

yellowblue See "Message Center" in the Index for further information. If the transmission fluid reaches temperatures of approximately 275_F (135_C) or greater, the message center will display a TRANS HOT...IDLE ENG warning message. Pull the vehicle off the roadway when it is safe to do so. Set the parking brake, place the transmission in PARK (P) and allow the engine to idle until the transmission temperature falls below 260_F (127_C). If the transmission continues to operate above 265_F (130_C), please contact your nearest dealer or the GM Roadside Assistance Center. The following situations can cause the transmission to operate at higher temperatures: D D D D D D Towing a trailer Hot outside air temperatures Hauling a large or heavy load Low transmission fluid level High transmission fluid level Restricted air flow to the radiator and the auxiliary transmission oil cooler (if equipped). NOTICE: If you keep driving your vehicle with the transmission temperature gage above the normal operating range, you can damage the transmission. This could lead to costly repairs that may not be covered under your warranty. A temporary solution to hotter transmission operating temperatures may be to let the transmission cool down. If the transmission is operated at higher temperatures on a frequent basis, see "Scheduled Maintenance" in the Index for the proper transmission maintenance intervals. 2-79