GMC Sierra Denali 2006 Owner's Manual page 151

At approximately 265°F (130°C), the message center
will display a TRANSMISSION HOT message and
the transmission will enter a transmission protection
mode. When the transmission enters the protection
mode, you may notice a change in the transmission
shifting patterns. The transmission will return to normal
shifting patterns when the transmission fluid temperature
falls below 260°F (127°C).
See Driver Information Center (DIC) on page 3-44 for
further information.
If the transmission fluid reaches temperatures of
approximately 275°F (135°C) or greater, the Driver
Information Center will display a TRANS HOT IDLE
ENGINE warning message, and a chime will sound.
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), contact your nearest dealer or the
GM Roadside Assistance Center. See Roadside
Assistance Program on page 7-6.
Notice: If you drive your vehicle with the
transmission temperature gage above normal
operating range, you can damage the transmission.
This could lead to costly repairs that would not
be covered by your warranty. Do not drive your
vehicle while the transmission temperature gage
reading is above normal. See your dealer for service.
The following situations can cause the transmission to
operate at higher temperatures:
•
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).
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 6-4 for the proper transmission maintenance
intervals.
3-37