2000 GMC YUKON oil temperature

2-18
CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the wrong
kind of extension cord could overheat and cause
a fire. You could be seriously injured. Plug the
cord into a properly grounded three
-prong
11 0
-volt AC outlet. If the cord won't reach,
use a heavy
-duty three-prong extension cord
rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and store
the cord as it was before to keep it away from moving
engine parts. If you don't, it could be damaged.
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature, the
kind of oil you have, and some other things. Instead of
trying to list everything here, we ask that you contact
your dealer in the area where you'll be parking your
vehicle. The dealer can give you the best advice for
that particular area.
Automatic Transmission Operation
There are several different positions for your shift lever.
Your vehicle is equipped with an automatic transmission
and features an electronic shift position indicator within
the instrument panel cluster. This display must be
powered anytime the shift lever is capable of being
moved out of PARK (P). This means that if your key is
in OFF, rather than LOCK, there will be a small current
drain on your battery which could discharge your battery
over a period of time. If you have to leave your key in
the ignition in OFF for an extended period, it is
recommended that you remove the IGN 0 fuse from the
instrument panel fuse block. See ªFuses and Circuit
Breakersº in the Index.

2-75
See ªMessage Centerº 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.
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.
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 ªScheduled Maintenanceº in the
Index for the proper transmission maintenance intervals.

2-80
Emissions Inspection and Maintenance Programs
Some state/provincial and local governments have or may
begin programs to inspect the emission control equipment
on your vehicle. Failure to pass this inspection could
prevent you from getting a vehicle registration.
Here are some things you need to know in order to help
your vehicle pass an inspection:
Your vehicle will not pass this inspection if the
SERVICE ENGINE SOON or CHECK ENGINE light is
on or not working properly.
Your vehicle will not pass this inspection if the OBD
(on
-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen
if you have recently replaced your battery or if your
battery has run down. The diagnostic system is designed
to evaluate critical emission control systems during
normal driving. This may take several days of routine
driving. If you have done this and your vehicle still
does not pass the inspection for lack of OBD system
readiness, see your dealer or qualified service center to
prepare the vehicle for inspection.
Oil Pressure Gage
United States Canada
The oil pressure gage shows the engine oil pressure in
psi (pounds per square inch) when the engine is running.
Canadian vehicles indicate pressure in kPa (kilopascals).
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.
A reading in the low pressure zone may be caused by a
dangerously low oil level or some other problem causing
low oil pressure. Check your oil as soon as possible. See
ªCheck Eng Oil Pressureº and ªEngine Oilº in the Index.

2-84
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 ªScheduled Maintenanceº in the
Index for the proper transmission maintenance intervals.TRANS HOT...IDLE ENGINE
Your vehicle has a transmission over-temperature
display contained in the message center.
If this warning message is
displayed, pull the vehicle
off the roadway when it is
safe to do so.
Set the parking brake and place the transmission in
PARK (P). Idle the engine until the message center no
longer displays a message. If idling the engine does not
turn the warning message off after 10 to 15 minutes,
contact your nearest dealer or the GM Roadside Assistance
Center. See ªRoadside Assistanceº in the Index.
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.

2-85
The following situations can cause the transmission to
operate at higher temperatures:

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).
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 ªScheduled Maintenanceº in the
Index for the proper transmission maintenance intervals.LOW COOLANT
This message is displayed
when the cooling system is
low on coolant.
The engine may overheat. See ªEngine Coolantº in the
Index and have your vehicle serviced as soon as you can.
CHECK COOLANT TEMP
This message is displayed
when the cooling system
temperature gets hot.
Check the coolant temperature gage and the coolant
level. See ªEngine Coolantº and ªEngine Coolant
Temperature Gageº in the Index. See ªEngine
Overheatingº in the Index for further information.

2-86 ENGINE OVERHEATED
This message is displayed
when the cooling system
temperature gets too hot.
This message will be displayed after the air conditioning
system has automatically turned off for the engine
coolant protection mode. See ªEngine Overheatingº
in the Index for further information.
REDUCED ENGINE POWER
This message is displayed
when the cooling system
temperature gets too hot
and the engine further
enters the engine coolant
protection mode.
See ªEngine Overheatingº in the Index for
further information.
CHECK ENG OIL PRESSURE
This message is displayed
when the engine oil pressure
is low.
See ªOil Pressure Gageº in the Index for more information.
CHECK ENG OIL LEVEL
This message is displayed
when the engine oil level
is low.
Once oil is added, it may need time to drain and settle in
the engine before this message will turn off. It is best to
let the engine cool down (if it is hot) or warm up (if it is
cold) and cycle the ignition to be sure this message turns
off. Refer to the dipstick for the correct level.
See ªEngine Oilº in the Index on how to check the oil
level and for what type of oil to add.

4-53
Your vehicle is equipped with a button at the end of
the shift lever which, when pressed, enables tow/haul.
Your vehicle may be equipped with Autoride which
further improves your vehicle's ride while towing.
See ªAutorideº in the Index for more information.
When the button is pressed, a light on the instrument
panel will illuminate to indicate that tow/haul has been
selected. Tow/haul may be turned off by pressing the
button again, at which time the indicator light on
the instrument panel will turn off. The vehicle will
automatically turn off tow/haul every time it is started.
Tow/haul is designed to be most effective when the vehicle
and trailer combined weight is at least 75% of the vehicle's
Gross Combined Weight Rating (GCWR). Tow/haul is
most useful under the following driving conditions:

When pulling a heavy trailer or a large or heavy load
through rolling terrain.

When pulling a heavy trailer or a large or heavy load
in stop and go traffic.

When pulling a heavy trailer or a large or heavy load
in busy parking lots where improved low speed
control of the vehicle is desired.
Operating the vehicle in tow/haul when lightly loaded
or with no trailer at all will not cause damage. However,
there is no benefit to the selection of tow/haul when the
vehicle is unloaded. Such a selection when unloaded may result in
unpleasant engine and transmission driving
characteristics and reduced fuel economy. Tow/haul is
recommended only when pulling a heavy trailer or a
large or heavy load.
Weight of the Trailer
How heavy can a trailer safely be?
It depends on how you plan to use your rig. For example,
speed, altitude, road grades, outside temperature and
how much your vehicle is used to pull a trailer are all
important. And, it can also depend on any special
equipment that you have on your vehicle.
Use one of the following charts to determine how much
your vehicle can weigh, based upon your vehicle model
and options.
Maximum trailer weight is calculated assuming only the
driver is in the tow vehicle and it has all the required
trailering equipment. The weight of additional optional
equipment, passengers and cargo in the tow vehicle
must be subtracted from the maximum trailer weight.
The engine oil cooler and the heavy
-duty trailering
package is required on C/K
-2500 models with the
VORTEC 6000 engine.

4-60 Making Turns
NOTICE:
Making very sharp turns while trailering could
cause the trailer to come in contact with the
vehicle. Your vehicle could be damaged. Avoid
making very sharp turns while trailering.
When you're turning with a trailer, make wider turns than
normal. Do this so your trailer won't strike soft shoulders,
curbs, road signs, trees or other objects. Avoid jerky or
sudden maneuvers. Signal well in advance.
Turn Signals When Towing a Trailer
The arrows on your instrument panel will flash whenever
you signal a turn or lane change. Properly hooked up, the
trailer lamps will also flash, telling other drivers you're
about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument panel
will flash for turns even if the bulbs on the trailer are burned
out. Thus, you may think drivers behind you are seeing
your signal when they are not. It's important to check
occasionally to be sure the trailer bulbs are still working.
Driving On Grades
Reduce speed and shift to a lower gear before you
start down a long or steep downgrade. If you don't shift
down, you might have to use your brakes so much that
they would get hot and no longer work well.
You can tow in DRIVE (D). You may want to shift the
transmission to THIRD (3) or, if necessary, a lower gear
selection if the transmission shifts too often (e.g., under
heavy loads and/or hilly conditions).
You may also want to activate the tow/haul mode if the
transmission shifts too often. See ªTow/Haul Modeº
in the Index.
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a
lower temperature than at normal altitudes. If you turn
your engine off immediately after towing at high altitude
on steep uphill grades, your vehicle may show signs
similar to engine overheating. To avoid this, let the
engine run while parked (preferably on level ground)
with the automatic transmission in PARK (P) for a few
minutes before turning the engine off. If you do get
the overheat warning, see ªEngine Overheatingº in
the Index.