1997 GMC SIERRA Owners Manual

Refer to the Maintenance Schedule to determine when to
replace the air filter. See “Owner Checks and Services”
in
the Index.
Operating the engine with the
air cleaner off
can cause you OF others to be burned. The air
cleaner not only cleans the air,
it stops flame if
the engine backfires.
If it isn’t there, and the
engine backfires, you could be burned. Don’t
drive with it
off, and be careful working on the
engine with the air cleaner
off.
I NOTICE:
If the air cleaner is off, a backfire can cause a
damaging engine fire. And, dirt can easily get
into your engine, which will damage it. Always
have the air cleaner in place when you’re driving.
Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic 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 CVWR 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.
In hilly or mountainous terrain.
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.
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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
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:
0 When outside temperatures are above 90°F (32°C).
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).
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 ( 10°C), drive the
vehicle
in THIRD (3) 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 must perform a hot check
before adding fluid. This will give you a more accurate
reading
of the fluid level.
0 At high speed for quite a while.
0 In heavy traffic -- especially in hot weather.
0 While pulling a trailer.
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Checking the Fluid Hot or Cold
Park your vehicle on a level place. Keep the
engine running.
With the parking brake applied, place the shift lever
in PARK
(P).
0 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). Then, without shutting
off the engine, follow these steps:
0 Let the
engine run at idle for three minutes or more.
1. The red transmission dipstick handle is located at the
rear
of the engine compartment, on the passenger's
side. 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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I
3. Check both sides of the dipstick, and read the lower
level. The fluid level must
be in the COLD area for a
cold check or in the HOT area or cross-hatched area
for a hot check.
4. If the fluid level is in the acceptable range, push the
dipstick back in all the way; then flip the handle
down to lock the dipstick in place.
How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind
of transmission fluid to use. See “Recommended
Fluids and Lubricants”
in the Index. Add
fluid only after checking the transmission fluid
HOT. (A COLD check is used only as a reference.) If the
fluid level is low, add only enough
of the proper fluid to
bring the level up to the
HOT area for a hot check. It
doesn’t take much fluid, generally less than one pint
(0.5 L). Don ’t ove@ZZ.
NOTICE:
We recommend you use only fluid labeled
DEXRON@-111, because fluid with that label is
made especially
for your automatic transmission.
Damage caused by fluid other than DEXRON-111
is not covered by your new vehicle warranty.
After adding fluid, recheck the fluid level as
described under
“HOW to Check.”
0 When the correct fluid level is obtained, push the
dipstick back in all
the way; then flip the handle
down to lock the dipstick
in place.
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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.
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
3. If the fluid level is good, install the plug and be sure
the
filler plug hole.
it
is fully seated. If the fluid level is low, add more
fluid as described
in the next steps.
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How to Add Fluid When to Check and What to Use
Here’s how to add
fluid. Refer to the Maintenance
Schedule to determine what kind of fluid to use. See
“Recommended Fluids and Lubricants” in the Index.
1. Remove the filler plug.
2. Add fluid at the filler plug hole. Add only enough
fluid to bring the fluid level
up to the bottom of the
filler plug hole.
3. Install the filler plug. Be sure the plug is fully seated.
Hydraulic Clutch
The hydraulic clutch system in your vehicle is
self-adjusting.
A slight amount of play (114 inch to
1/2 inch or 6 mm to 12 mm) in the pedal is normal.
It isn’t
a good idea to “top off’ your clutch fluid. Adding
fluid won’t correct
a leak. A fluid loss in this system
could indicate a problem. Have the system inspected
and repaired. Refer
to the Maintenance
yk I Schedule, Owner Checks
and
Services,
to determine
how often you should check
the fluid level in your clutch
master cylinder reservoir
and for the proper fluid.
See “Owner Checks
and Services” and “Recommended Fluids and
Lubricants” in the Index.
How to Check
The proper fluid 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.
Rear 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.
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How to Check Lubricant
If the level is below the bottom of the filler plug hole,
you’ll need to add
some lubricant. Add enough lubricant
to raise the level
to the bottom of 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.
C3 (3500 HD) Trucks Equipped with
Dana Rear Axle
Additional rear axle scheduled maintenance is required
on
3500 HD models equipped with Dana rear axles
when they are driven under the following conditions:
Extreme loading (at or near GVWR) or trailer
Operation above 45 mph (70 km/h) for extended
towing, and:
periods of time.
Vehicles used in any
of these conditions require the rear
axle lubricant be changed every
30,000 miles (50 OOO km).
Fluid capacity is 4.12 quarts (3.9 L).
Four-wheel Drive
Most lubricant checks in this section also apply to
four-wheel-drive vehicles. However, they have two
additional systems that need lubrication.
Transfer Case
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant. See “Periodic Maintenance
Inspections” in the Index.
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How to Check Lubricant Front Axle
If the level is below the bottom of the filler plug hole,
you’ll need to add some lubricant. Add enough lubricant
to raise the level
to the bottom of 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.
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.
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