GMC Sierra Denali Owner's Manual page 162

See Driver Information Center (DIC) on page 3-43 for
further information.
If the transmission fluid reaches temperatures of
approximately 275°F (1 35°C) or greater, the Driver
Information Center wiil 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
(1 27°C). If the transmission continues to operate
above 265°F (13O"C), contact your nearest dealer or
the GM Roadside Assistance Center. See Roadside
Assistance Program
on
page 7-5.
Notices 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.
The following situations can cause the transmission to
operate at higher temperatures:
0
Towing a trailer
0
Hot outside air temperatures
0
Hauling a large or heavy load
0
Low transmission fluid level
High transmission fluid level
0
Restricted air flow to the radiator and the auxiliary
transmission oil cooler (if equipped).
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
on page 6-5 for the proper transmission maintenance
intervals.
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