1999 Chevrolet Silverado 1500 Pickup Owner's Manual - Page 156

yellowblue NOTICE: If you keep driving your vehicle with the transmission TRANS HOT...IDLE ENGINE message displayed, you can damage the transmission. This could lead to costly repairs that may not be covered under your warranty. The following situations can cause the transmission to operate at higher temperatures: LOW COOLANT This message is displayed when the cooling system is low on coolant. D D D D D D The engine may overheat. See "Engine Coolant" in the Index and have your vehicle serviced as soon as you can. Towing a trailer Hot outside air temperatures Hauling a heavy load Low transmission fluid level High transmission fluid level Restricted air flow to the radiator and the auxiliary transmission oil cooler (if equipped). CHECK COOLANT TEMP This message is displayed when the cooling system temperature gets hot. 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. Check the coolant temperature gage and the coolant level. See "Engine Coolant" and "Engine Coolant Temperature Gage" in the Index. See"Engine Overheating" in the Index for further information. 2-84