2004 CHEVROLET TAHOE ECU

{CAUTION:
Do not load your vehicle any heavier than the
GVWR, or either the maximum front or rear
GAWR. If you do, parts on your vehicle can
break, and it can change the way your vehicle
handles. These could cause you to lose
control and crash. Also, overloading can
shorten the life of your vehicle.
Notice:Overloading your vehicle may cause
damage. Repairs would not be covered by your
warranty. Do not overload your vehicle.
The label will help you decide how much cargo and
installed equipment your truck can carry.
Using heavier suspension components to get added
durability might not change your weight ratings. Ask your
dealer to help you load your vehicle the right way.
If you put things inside your vehicle – like suitcases,
tools, packages, or anything else – they go as fast
as the vehicle goes. If you have to stop or turn quickly,
or if there is a crash, they’ll keep going.
{CAUTION:
Things you put inside your vehicle can strike
and injure people in a sudden stop or turn, or
in a crash.
Put things in the cargo area of your
vehicle. Try to spread the weight evenly.
Never stack heavier things, like suitcases,
inside the vehicle so that some of them
are above the tops of the seats.
Do not leave an unsecured child restraint
in your vehicle.
When you carry something inside the
vehicle, secure it whenever you can.
Do not leave a seat folded down unless
you need to.
There’s also important loading information for off-road
driving in this manual. See″Loading Your Vehicle
for Off-Road Driving″in the Index.
4-63

Driving with a Trailer
{CAUTION:
If you have a rear-most window open and you
pull a trailer with your vehicle, carbon
monoxide (CO) could come into your vehicle.
You can not see or smell CO. It can cause
unconsciousness or death. SeeEngine
Exhaust on page 2-43. To maximize your safety
when towing a trailer:
Have your exhaust system inspected for
leaks, and make necessary repairs before
starting on your trip.
Keep the rear-most windows closed.
If exhaust does come into your vehicle
through a window in the rear or another
opening, drive with your front, main
heating or cooling system on and with the
fan on any speed. This will bring fresh,
outside air into your vehicle. Do not use
the climate control setting for maximum air
because it only recirculates the air inside
your vehicle. SeeClimate Control System
on page 3-22.Towing a trailer requires a certain amount of experience.
Before setting out for the open road, you’ll want to get
to know your rig. Acquaint yourself with the feel of
handling and braking with the added weight of the trailer.
And always keep in mind that the vehicle you are
driving is now a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you start, check all trailer hitch parts and
attachments, safety chains, electrical connector, lamps,
tires and mirror adjustment. If the trailer has electric
brakes, start your vehicle and trailer moving and then
apply the trailer brake controller by hand to be sure
the brakes are working. This lets you check your
electrical connection at the same time.
During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer
brakes are still working.
4-74

Coolant Surge Tank Pressure Cap
SeeEngine Compartment
Overview on page 5-14for
more information on
location.
The coolant surge tank pressure cap must be fully
installed on the coolant surge tank.
Notice:If the pressure cap is not tightly installed,
coolant loss and possible engine damage may
occur. Be sure the cap is properly and tightly
secured.
Engine Overheating
You will nd a coolant temperature gage on your
vehicle’s instrument panel. SeeEngine Coolant
Temperature Gage on page 3-47. In addition, you will
nd an ENGINE OVERHEATED, and a REDUCED
ENGINE POWER message in the DIC on the instrument
panel. SeeDriver Information Center (DIC) on
page 3-56.
Overheated Engine Protection
Operating Mode (V8 Engines Only)
If an overheated engine condition exists and the
REDUCED ENGINE POWER message is displayed, an
overheat protection mode which alternates ring
groups of cylinders helps prevent engine damage. In
this mode, you will notice a loss in power and engine
performance. This operating mode allows your vehicle to
be driven to a safe place in an emergency. Driving
extended miles (km) and/or towing a trailer in the
overheat protection mode should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any
repair. The engine oil will be severely degraded.
Repair the cause of coolant loss, change the oil and
reset the oil life system. SeeEngine Oil on page 5-17.
5-29

10. Set all four tires to the recommended air pressure
level as indicated on the Certication/Tire label or
the Tire and Loading Information label.
11. Put the valve caps back on the valve stems
The spare tire does not have a TPM sensor. If you
replace one of the road tires with the spare, the CHECK
TIRE PRESSURE message will be displayed on the DIC
screen. This message should go off once you re-install
the road tire containing the TPM sensor. The SVC TIRE
MONITOR message is displayed when the TPM system
is malfunctioning. One or more missing or inoperable
TPM sensors will cause the service tire monitor message
to be displayed. See your dealer for service.
Federal Communications Commission and
Industry and Science Canada
The TPM system operates on a radio frequency subject
to Federal Communications Commission (FCC) Rules
and with Industry and Science Canada.
This device complies with Part 15 of the FCC Rules
and with RSS-210 of Industry and Science Canada.
Operation is subject to the following two conditions:
(1) This device may not cause harmful interference, and
(2) this device must accept any interference received
including interference that may cause undesired
operation of the device.Changes or modications to this system by other than
an authorized service facility could void authorization to
use this equipment.
Tire Inspection and Rotation
Tires should be rotated every 5,000 to 8,000 miles
(8 000 to 13 000 km).
Any time you notice unusual wear, rotate your tires as
soon as possible and check wheel alignment. Also
check for damaged tires or wheels. SeeWhen It Is Time
for New Tires on page 5-74andWheel Replacement
on page 5-77for more information.
Make sure the spare tire is stored securely. Push, pull,
and then try to rotate or turn the tire. If it moves, use the
ratchet/wheel wrench to tighten the cable. SeeChanging
a Flat Tire on page 5-80.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The rst rotation
is the most important. SeeScheduled Maintenance
on page 6-4.
5-72

Tire Chains
{CAUTION:
If your vehicle has P265/75R16, LT265/75R16,
P265/70R16 or P265/70R17 size tires, don’t use
tire chains. They can damage your vehicle
because there’s not enough clearance. Tire
chains used on a vehicle without the proper
amount of clearance can cause damage to the
brakes, suspension or other vehicle parts.
The area damaged by the tire chains could
cause you to lose control of your vehicle and
you or others may be injured in a crash.
Use another type of traction device only
if its manufacturer recommends it for use on
your vehicle and tire size combination and
road conditions. Follow that manufacturer’s
instructions. To help avoid damage to your
CAUTION: (Continued)
CAUTION: (Continued)
vehicle, drive slowly, readjust or remove the
device if it’s contacting your vehicle, and don’t
spin your wheels.
If you do nd traction devices that will t,
install them on the rear tires.
Notice:If you have a tire size other than P265/75R16,
LT265/75R16, P265/70R16 or P265/70R17 use tire
chains only where legal and only when you must.
Use chains that are the proper size for your tires.
Install them on the rear tires only.
Don’t use chains on the front tires.
Tighten them as tightly as possible with the ends
securely fastened. Drive slowly and follow the chain
manufacturer’s instructions. If you can hear the
chains contacting your vehicle, stop and retighten
them. If the contact continues, slow down until
it stops. Driving too fast or spinning the wheels
with chains on will damage your vehicle.
5-79

4. Insert the hoist end (F)
through the hole (G)
in the rear bumper and
into the hoist shaft.
5. Raise the tire part way upward. Make sure the
retainer is seated in the wheel opening.
6. Raise the tire fully against the underside of the
vehicle by turning the wheel wrench clockwise
until you hear two clicks or feel it skip twice. You
cannot overtighten the cable.A. Push and Pull B. Turn Tire
7. Make sure the tire is stored securely. Push, pull,
and then try to turn the tire. If the tire moves, use
the wheel wrench to tighten the cable. Reinstall the
spare tire lock (if equipped).
5-94

To store the tools, follow these procedures:
For Tahoe, do the following:
1. Put the tool kit, with the jack tools and gloves, in
the tool bag and place in the retaining clip above
the jack.
2. Tighten down with the wing nut.
3. Then, assemble wheel chocks and bottle jack
together with the wing nut and retaining hook.
4. Position behind the jack storage cover in the left
rear side panel and tighten, adjusting clockwise
until the jack is secured tight in the mounting
bracket. Be sure to position the holes in the base
of the jack onto the pin in the mounting bracket.
For Suburban, do the following:
1. Return the tool kit (jack tools and gloves) to the
tool bag.
2. Assemble wheel chocks and jack together with the
wing nut and retaining hook.
3. Position under the jack storage tray in the left rear
side panel below the wheelbase and tighten,
adjusting clockwise until the jack is secured tight in
the mounting bracket. Be sure to position the holes
in the base of the jack onto the pin in the mounting
bracket.4. Use the retaining clip to fasten the tool kit on the stud
in the storage compartment in the rear left trim panel
and turn the wing nut clockwise to secure.
5. Return the storage tray.
A. Tool Kit with Jack Tools
B. Retaining Bracket
and Wing Nut
C. Wing Nut Holding
Tire BlocksD. Tire Blocks
E. Jack Tahoe (Rear Access Panel)
5-95

7. Place the bottom edge of the jack on the wheel
blocks, separating them so that the jack is
balanced securely.
8. Attach the jack handle, extension, and wheel
wrench to the jack and place it (with the wheel
blocks) under the vehicle towards the front of the
rear bumper. Position the center lift point of the jack
under the center of the spare tire.
9. Turn the wrench clockwise to raise the jack until it
lifts the end tting.
10. Continue raising the jack until the spare tire stops
moving upward and is held rmly in place. The
secondary latch has released and the spare tire is
balancing on the jack.
5-98