1996 GMC SIERRA engine

Automatic Transmission Fluid
When to Check a1 C’ -ge
A good time to check your auromarlc transmission fluid
level
is when the engine oil is changed.
Change both the fluid and filter every
50,000 miles
(83 000 km) if the vehicle’s GVWR is over 8,600 or
if the vehicle is mainly driven under one or more of
these conditions:
In heavy city traffic where the outside temperature
regularly reaches
90°F (32°C) or higher.
0 In hilly or mountainous terrain.
0 When doing frequent trailer towing.
Uses such as found in taxi, police or delivery service.
If your vehicle’s GVWR is not over 8,600 and you do
not use your vehicle under any of these conditions, the
fluid and filter
do not require changing.
See “Scheduled Maintenance Services’’
in the Index.
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 on the dipstick.
NOTICE:
Too much or too little fluid can damage your
transmission.
Too much can mean that some of
i the fluid could come out and fall on hot engine
~ parts or exhaust system parts, starting a fire. Be
sure to get an accurate reading if you check your
transmission fluid.
Wait at least 30 minutes before checking the
transmission fluid level
if you have been driving:
When outside temperatures are above 90°F (32°C).
0 At high speed for quite a while.
In heavy traffic -- especially in hot weather.
While pulling a trailer.
To get the right reading, the fluid should be at normal
operating temperature, which
is 180°F to 200°F (82°C
to 93°C).
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Checking Transmission Fluid Hot
Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50°F
(10°C). If it's colder than 50°F (lO"C), drive the
vehicle
in DRIVE (D) until the engine temperature
gage moves and then remains steady for
10 minutes.
Then
follow the hot check procedures.
Checking Transmission Fluid Cold
A cold check is made after the vehicle has been sitting
for eight hours or more with the engine off and is used
only
as a reference. Let the engine run at idle for five
minutes
if outside temperatures are 50°F (10°C) or
more. If it's colder than 50°F (lO"C), you may have to
idle the engine longer. Should
the fluid level be low
during a cold check, you nwst perform a hot check
before adding fluid. This will give you
a more accurate
reading
of the fluid level.
Checking the Fluid Hot or Cold
0 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 red transmission dipstick handle
is located at the
rear
of the engine compartment, on the passenger side.
I. 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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Manual Transmission Fluid
When to Check
A good time to have it checked is when the engine
oil
is changed. However, the fluid in your manual
transmission doesn’t require changing.
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 fluid can damage your
transmission.
Too much can mean that some of
the fluid could come out and fall on hot engine
parts or exhaust system parts, starting a fire.
Be
sure to get an accurate reading if you check your
transmission fluid.
II
Check the fluid 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 fingers on the
transmission case.
Then, follow these steps:
1. Remove the filler plug.
2. Check that the lubricant level is up to the bottom of
the filler plug hole.
3. If the fluid level is good, install the plug and be sure
it is fully seated. If the fluid level is low, add more
fluid as described in the next steps.
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Front Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how
often
to check the lubricant and when to change it. See
"Scheduled Maintenance Services"
in the Index.
How to Check Lubricant
If the level is below the bottom of the filler plug hole.
you'll
need to add some lubricant.
If the differential is at operating temperature (warm),
add enough lubricant
to raise the level to the bottom of
the filler plug hole.
If the differential is cold, add enough lubricant to raise
the level
to 1/2 inch (1 2 mm) below the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind
of lubricant to use. See "Recommended Fluids and
Lubricants"
in the Index.
Engine Coolant
The cooling system in your vehicle is filled with new
DEX-COOL
TM (orange-colored, silicate-free) engine
coolant. This coolant is designed
to remain in your
vehicle for
5 years or 100,000 miles (1 66 000 km),
whichever occurs first.
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"
in
the Index.
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A 50/50 mixture of water and the proper coolant for
your vehicle
will:
Give freezing prorecrlon down to -34°F (-37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning gages work as they should.
NOTICE:
When adding coolant it is important that you use
DEX-COOL TM (orange-colored, silicate-free)
coolant meeting
GM Specification 6277M.
If silicated coolant is 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 first. use
a mixture
of one-half dum wwter (preferably
distilled) and one-half
DEX-COOL” (orange-colored.
silicate-free) antifreeze that meets
GM Specification
6277M. which
won‘t damage aluminum parts. Use
GM Engine Coolant Supplement (sealer) (GM Part
No. 363462 1 ) with any complete coolant change. If you
use this mixture.
you don’t need to add anything else.
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mix will. Your vehicle’s coolant warning
system
is set for the proper coolant mix. With
plain water or the wrong mix, your engine could
get
too hot but you wouldn’t get the overheat
warning. Your engine could catch fire and you or
others could be burned. Use a
50150 mix of clean
water and
DEX-COOL TM (orange-colored,
silicate-free) antifreeze.
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NOTICE:
If you use an improper coolant mix, your engine
could overheat and be badly damaged. The
repair cost wouldn't be covered by your
warranty.
Too much water in the mix can freeze
and crack the engine, radiator, heater core and
other parts.
If you have to add coolant more than four times 8 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.
Checking Coolant
If your vehicle has a diesel engine, see "Clwcking
Coolant"
in the Diesel Engine Supplement.
d
The coolant recovery tank is located on the passenger
side at the rear corner of the engine compartment.
When your engine
is cold, the coolant level should be at
the
COLD mark, or a little higher. When your engine is
warm. the level sho~~ld be up to the HOT mark, or a
little higher.
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Adding Coolant
If you need more coolant, add the proper mix ut tho
cYN-hnt Ix~c'olY!l'\: tmk.
A CAUTION:
\---- -
Turning the radiator pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. With the coolant recovery tank, you will
almost never have to add coolant at the radiator. Never turn the radiator pressure cap
-- even a
little
-- when the engine and radiator are hot.
Add coolant mix at the recovery tank, but be careful not
to spill it.
/rl CAUTION:
r -4
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.
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Radiator Pressure Cap
(Gasoline Engine)
The radiator pressure cap must be tightly installed with
the arrows on the cap lined LIP with the overflow tube on
the radiator filler neck.
NOTICE:
Your radiator cap is a 15 psi (105 kPa)
pressure-type cap and must be tightly installed
to prevent coolant
loss and possible engine
damage from overheating. Be sure the arrows
on the
cap line up with the overflow tube on the
radiator filler neck.
Thermostat
Engine coolant temperature is controlled by a thermostat
in the engine coolant system. The thermostat stops the
flow of coolant through the radiator until the coolant
reaches
a preset temperature.
When you replace your thermostat, an AC@ thermostat
is recommended.
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