1998 GMC ENVOY transmission

When you lift the hood, you’ll see these items:
C
A. Battery
B. Coolant Recovery Tank
C. Engine
Oil Dipstick
D. Engine
Oil Fill
E. Transmission Dipstick
E Power Steering Reservoir
G. Brake Master Cylinder
H. Air Cleaner
I. Fuse Block
J. Windshield Washer Fluid
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A CAUTION:
Operating the engine with the air cleaner off can
cause you or 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.
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
15,000 miles
(25 000 km) 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 you do not use your vehicle under any of these
conditions, change the fluid and filter every
50,000 miles (83 000 km).
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:
When outside temperatures are above 90°F (32°C).
0 At high speed for quite a while.
0 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). See “Checking Transmission Fluid
Hot”
in the Index.
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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 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
1nust 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
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:
1. The transmission
dipstick has a red
handle and
is located at
the rear of the engine
compartment.
Flip the
handle up and then pull
out the dipstick and
wipe
it with a clean rag
or paper towel.
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2. Push it back in all the way, wait three seconds and
then pull it back
out again.
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
while it is 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). Dun ’t overfiill.
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-I11
is not covered by your new vehicle warranty.
0 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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FuseKircuit Usage
Breaker
2
3
4
8
9
10
11
12 Cigarette
Lighter, Data
Link Connector
Cruise Control Module and
Switch, Body Control Module,
Heated Seats
Gages, Body Control Module,
Instrument Panel Cluster
Interior Lights
Not Used
Power Outside Mirror, Power
Lock Relay
Courtesy Lamps, Battery
Run-Down Protection
Not Used
Turn Signal
Cluster, Engine Control Module
Parking Lamps, Power Window
Switch, Body Control Module,
Ashtray Lamp
FuseKircuit
Breaker
13
14
15
16
17
18
19
20
21
22
23
24
Usage
Auxiliary Power
Power Locks Motor
4WD Switch, Engine Controls (VCM, PCM, Transmission)
Air Bag
Front Wiper
Not Used
Radio Battery
Amplifier
HVAC
I (Automatic), HVAC
Sensors (Automatic)
Anti-Lock Brakes
Rear Wiper
Radio, Ignition
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Name
RT TRN
RR PRK
TRL PRK
LT HDLP
RT HDLP
LT HI
RT HI
FR PRK
INT BAT
ENG
I
ECM B
ABS
ECM
1
HORN
BTS
I
BIU LP
IGN E
AIC
RAP
OXYSEN
Usage
Right Turn Signal Rear
Right Rear Parking Lamps
Trailer Park Lamps Left Headlamp
Right Headlamp
Left High Beam
Right High Beam
Front Parking Lamps
I/P Fuse Block Feed
Engine SensorsISolenoids, MAP,
CAM. PURGE, VENT
Engine Control Module, Fuel Pump,
Module, Oil Pressure
Anti-Lock Brake System
Engine Control Module Injectors Horn
Brake-Transmission Shift Interlock
Back-up
Lalllps
Engine
Air Conditioning
Retained Accessory Power
Oxygen Sensor
Name
IGN B
DRL
FOG LP
IGN
A
STUD #2
PARKLP
LR PRK
IGN C
HTDSEAT ATC
RRDFOG
HVAC
TRCHMSL
RR W/W
CRANK
LD LEV
HI BEAM
HAZLP
VECHMSL
HTDMIR
STOPLP
TBC
Usage
Column Feed, IGN 2, 3,4
Daytime Running Lamps
Fog Lamps
Starting and Charging IGN
I
Accessory Feeds, Electric Brake
Parking La~nps
Left Rear Parking Lamps Starter Solenoid, Fuel Pump. PRNDL
Heated Seat
Electronic Transfer Case
Rear Defogger
HVAC System
Trailer Center High Mount Stop Light
Rear Window Wiper
Clutch Switch, NSBU Switch
Electronic Load Leveling
HID Headlamps Hazard Lamps
Vehicle Center High
Mount Stop Lamp
Heated Mirror
Stoplamps
Truck Body Computer
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Normal Maintenance Replacement Parts
Replacement part numbers listed in this section are
based on the latest information available at the time of
printing, and are subject
to change. If a part listed in this
manual is not the same as the part used in your vehicle
when it was built, or if you have any questions, please
contact your GMC dealer.
Thermostat
......................... 1255905 1
Oil Filter ............................... PF52
Air Cleaner Filter
...................... A1 163C
PCV Valve
.......................... CV746C
Automatic Transmission Filter Kit
...... 24200796
Spark Plugs
.......................... .41-932
Fuel Filter
............................. GF48 1
Front Windshield Wiper Blade
................ Trico (20 inched50.8 cm)
Backglass Wiper Blade . . Trico (14 inched35.6 cm)
Capacities (Approximate)
Cooling System* ............. 11.7 quarts (1 1.1 L)
Crankcase* ................... 4.5 quarts (4.3 L)
Automatic Transmission
(Drain and Refill)*
........... 5.0 quarts (4.7 L)
Differential Fluid ............................
Front ....................... 2.6 pints (1.2 L)
Rear ........................ 4.0 pints ( 1.9 L)
Fuel Tank ..................... 18 gallons (68 L)
A/C Refrigerant ........... 30 oz. or 2 lbs. (0.9 kg)
of R- 134a
*After refill, the level
must be checked.
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