2003 CHEVROLET SILVERADO engine

Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50ÉF
(10ÉC). If it's colder than 50ÉF (10ÉC), drive the vehicle
in THIRD (3) until the engine temperature gage
moves and then remains steady for 10 minutes.
A cold ¯uid check can be made after the vehicle has
been sitting for eight hours or more with the engine off,
but this is used only as a reference. Let the engine
run at idle for ®ve minutes if outside temperatures are
50ÉF (10ÉC) or more. If it's colder than 50ÉF (10ÉC), you
may have to idle the engine longer. Should the ¯uid
level be low during this cold check, you
mustcheck the
¯uid hot before adding ¯uid. Checking the ¯uid hot
will give you a more accurate reading of the ¯uid level.
Checking the Fluid Level
Prepare your vehicle as follows:
·Park your vehicle on a level place. Keep the engine
running.
·With the parking brake applied, place the shift lever
in PARK (P).
·With your foot on the brake pedal, move the shift
lever through each gear range, pausing for about
three seconds in each range. Then, position the shift
lever in PARK (P).
·Let the engine run at idle for three minutes or more.Then, without shutting off the engine, follow these steps:
The transmission dipstick
handle with the graphic is
located at the rear of
the engine compartment,
on the passenger's side.
See
Engine Compartment Overview on page 5-10for
more information on location.
1. Flip the handle up and then pull out the dipstick
and wipe it with a clean rag or paper towel.
2. Push it back in all the way, wait three seconds and
then pull it back out again.
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Automatic Transmission Fluid
(Allison Transmission
ž)
When to Check and Change
A good time to check your automatic transmission ¯uid
level is when the engine oil is changed.
Change both the ¯uid and ®lter every 25,000 miles
(41 500 km) if the vehicle is mainly driven under one or
more of these conditions:
·In heavy city traffic where the outside temperature
regularly reaches 90ÉF (32ÉC) or higher.
·In hilly or mountainous terrain.
·When doing frequent trailer towing.
·Uses such as found in taxi, police or delivery
service.
If you do not use your vehicle under any of these
conditions, change the ¯uid and ®lter every
50,000 miles (83 000 km).
See
Part A: Scheduled Maintenance Services on
page 6-4.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service
department.If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too little ¯uid can damage
your transmission. Too much can mean that some
of the ¯uid could come out and fall on hot engine
part or exhaust system parts, starting a ®re.
Too little ¯uid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmission ¯uid.
Wait at least 30 minutes before checking the
transmission ¯uid level if you have been driving:
·When outside temperatures are above 90ÉF (32ÉC).
·At high speed for quite a while.
·In heavy traffic ± especially in hot weather.
·While pulling a trailer.
Checking the Fluid Level
Prepare your vehicle as follows:
·Park your vehicle on a level place. Keep the engine
running.
·With the parking brake applied, place the shift lever
in PARK (P).
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·With your foot on the brake pedal, run the engine for
at least once minute and shift to DRIVE (D). Then
shift to NEUTRAL (N) and then REVERSE (R) to ®ll
the hydraulic system. Then, position the shift lever in
PARK (P).
·Allow the engine to run at idle (500±800 rpm). Slowly
release the brake pedal.
Then, without shutting off the engine, follow these steps:
Cold Check Procedure
The purpose of the cold check is to determine if the
transmission has enough ¯uid to be operated safely until
a hot check can be made. The ¯uid level rises as ¯uid
temperature increases. DO NOT ®ll above the COLD
CHECK band if the transmission ¯uid is below normal
operating temperatures.
1. Pull out the dipstick and wipe it with a clean rag or
paper towel.
2. Push it back in all the way, wait three seconds and
then pull it back out again.
3. Check the ¯uid level reading. Repeat the check
procedure to verify the reading.
4. If the ¯uid level is within the COLD CHECK band,
the transmission may be operated until the ¯uid is
hot enough to perform a hot check. If the ¯uid
level is not within the COLD CHECK band, add or
drain ¯uid as necessary to bring the level into
the middle of the COLD CHECK band.5. Perform a hot check at the ®rst opportunity after the
normal operating temperature of 160ÉF (71ÉC) to
200ÉF (93ÉC) is reached.
6. If the ¯uid level is in the acceptable range, push the
dipstick back in all the way.
Hot Check Procedure
The ¯uid must be hot to ensure an accurate check. The
¯uid level rises as temperature increases.
1. Operate the transmission in DRIVE (D) range until
the normal operating temperature of 160ÉF (71ÉC)
to 200ÉF (93ÉC) is reached.
2. Pull out the dipstick and wipe it with a clean rag or
paper towel.
3. Push it back in all the way, wait three seconds and
then pull it back out again. Repeat the check
procedure to verify the reading.
4. Safe operating level is within the HOT RUN band
on the dipstick. The width of the HOT RUN band
represents approximately 1.06 quart (1.0 liter)
of ¯uid at normal operating temperature.
5. If the ¯uid level is not within the HOT RUN band,
add or drain ¯uid as necessary to bring the ¯uid
level to within the HOT RUN band.
6. If the ¯uid level is in the acceptable range, push the
dipstick back in all the way.
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Consistency of Readings
Always check the ¯uid level at least twice using the
procedures described previously. Consistency
(repeatable readings) is important to maintaining proper
¯uid level. If inconsistent readings persist, check the
transmission breather to be sure it is clean and
unclogged. If readings are still inconsistent, contact your
dealer.
How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission ¯uid to use. SeePart D:
Recommended Fluids and Lubricants on page 6-19.
Add ¯uid only after checking the transmission ¯uid while
it is hot. (A cold check is used only as a reference.) If
the ¯uid level is low, add only enough of the proper ¯uid
to bring the level up to the HOT area for a hot check.
It doesn't take much ¯uid, generally less than one
pint (0.5 L).
Don't over®ll.
Notice:
We recommend you use only ¯uid labeled
DEXRONž-III, because ¯uid with that label is
made especially for your automatic transmission.
Damage caused by ¯uid other than DEXRON
ž-III is
not covered by your new vehicle warranty.
·After adding ¯uid, recheck the ¯uid level as
described under
How to Check.
·When the correct ¯uid level is obtained, push the
dipstick back in all the way.
Manual Transmission Fluid
When to Check
A good time to have it checked is when the engine oil is
changed. See your maintenance schedule to ®nd out
when to change your transmission ¯uid.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at your GM dealership
service department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading.
Notice:Too much or too little ¯uid can damage
your transmission. Too much can mean that some
of the ¯uid could come out and fall on hot engine
part or exhaust system parts, starting a ®re.
Too little ¯uid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmission ¯uid.
Check the ¯uid level only when your engine is off, the
vehicle is parked on a level place and the transmission
is cool enough for you to rest your ®ngers on the
transmission case.
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Then, follow these steps:
1. Remove the ®ller plug.
2. Check that the lubricant level is up to the bottom of
the ®ller plug hole.
3. If the ¯uid level is good, install the plug and be sure
it is fully seated. If the ¯uid level is low, add more
¯uid as described in the next steps.How to Add Fluid
Here's how to add ¯uid. Refer to the Maintenance
Schedule to determine what kind of ¯uid to use. See
Part D: Recommended Fluids and Lubricants on
page 6-19.
1. Remove the ®ller plug.
2. Add ¯uid at the ®ller plug hole. Add only enough
¯uid to bring the ¯uid level up to the bottom of the
®ller plug hole.
3. Install the ®ller plug. Be sure the plug is fully
seated.
Hydraulic Clutch
The hydraulic clutch linkage in your vehicle is
self-adjusting. The clutch master cylinder reservoir is
®lled with hydraulic clutch ¯uid.
It is not necessary to regularly check clutch ¯uid unless
you suspect there is a leak in the system. Adding
¯uid won't correct a leak.
A ¯uid loss in this system could indicate a problem.
Have the system inspected and repaired. 5±speed for VORTECŸ 4300 V6 and
4800 V8 Engines Shown, Other Manual
Transmissions Similar
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When to Check and What to Use
The clutch master cylinder
reservoir is located in the
rear of the engine
compartment on the
driver's side of the vehicle.
See
Engine Compartment
Overview on page 5-10
for more information
on location.
Refer to the Maintenance Schedule to determine how
often you should check the ¯uid level in your clutch
master cylinder reservoir and for the proper ¯uid. See
Part B: Owner Checks and Services on page 6-12andPart D: Recommended Fluids and Lubricants on
page 6-19.
How to Check and Add Fluid
The proper ¯uid should be added if the level does not
reach the bottom of the diaphragm when it's in place in
the reservoir. See the instructions on the reservoir cap.
Engine Coolant
The cooling system in your vehicle is ®lled with
DEX-COOLžengine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occurs ®rst, if you add only
DEX-COOL
žextended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem
with engine overheating, see
Engine Overheating on
page 5-33.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
žcoolant will:
·Give freezing protection down to-34ÉF (-37ÉC).
·Give boiling protection up to 265ÉF (129ÉC).
·Protect against rust and corrosion.
·Help keep the proper engine temperature.
·Let the warning lights and gages work as they
should.
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Notice:When adding coolant, it is important that
you use only DEX-COOLž(silicate-free) coolant.
If coolant other than DEX-COOLžis added to
the system, premature engine, heater core or
radiator corrosion may result. In addition, the engine
coolant will require change sooner -- at 30,000 miles
(50,000 km) or 24 months, whichever occurs ®rst.
Damage caused by the use of coolant other
than DEX-COOL
žis not covered by your new vehicle
warranty.
What to Use
Use a mixture of one-halfclean, drinkable waterand
one-half DEX-COOLžcoolant which won't damage
aluminum parts. If you use this coolant mixture,
you don't need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle's coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch ®re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
žcoolant.
Notice:If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost wouldn't be covered by your
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core and
other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
Notice:If you use the proper coolant, you don't
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
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Checking Coolant
The coolant surge tank is
located in the engine
compartment on the
passenger's side of the
vehicle. See
Engine
Compartment Overview on
page 5-10
for more
information on location.
{CAUTION:
Turning the surge tank pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. Never turn the surge tank pressure
cap Ð even a little Ð when the engine and
radiator are hot.The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the FULL
COLD mark.
If your vehicle is equipped with a low coolant sensor,
and the LOW COOLANT LEVEL message comes
on and stays on, it means you're low on engine coolant.
See ªLow Coolant Levelº under
DIC Warnings and
Messages on page 3-65.
Adding Coolant
If you need more coolant, add the proper DEX-COOLž
coolant mixtureat the surge tank, but only when the
engine is cool.
{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol,
and it will burn if the engine parts are hot
enough. Don't spill coolant on a hot engine.
When replacing the pressure cap, make sure it is
hand-tight.
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