transmission fluid GMC SUBURBAN 1999 User Guide

6-17
3. Remove the air filter by pulling downward on the
element. Remove the second portion of the air filter
by sliding it towards the rear of the vehicle and then
pulling downward.
4. Install the new filter by reversing the steps listed
previously. Be sure to follow any instructions that
may be included in the replacement filter package.
Refer to the Maintenance Schedule to determine
when to replace the passenger compartment air filter.
See ªScheduled Maintenanceº in the Index.
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 is mainly driven under one
or more of these conditions:

In heavy city traffic where the outside temperature
regularly reaches 90F (32C) 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
100,000 miles (166 000 km).
See ªScheduled Maintenance Servicesº in the Index.
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 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.

6-18
Wait at least 30 minutes before checking the
transmission fluid level if you have been driving:

When outside temperatures are above 90F (32C).

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 180F to
200F (82C to 93C).
Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above
50F (10C). If it's colder than 50F (10C),
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 50F (10C) or
more. If it's colder than 50F (10C), 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.
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.

6-19
Then, without shutting off the engine, follow these steps:
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.
3. Check both sides of the dipstick, and read the lower
level. The fluid level must be in the COLD area,
below the cross
-hatched 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.

6-20 How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission fluid to use. See ªRecommended
Fluids and Lubricantsº 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). Don't overfill.
NOTICE:
We recommend you use only fluid labeled
DEXRON-III, because fluid with that label is
made especially for your automatic transmission.
Damage caused by fluid other than DEXRON
-III
is not covered by your new vehicle warranty.

After adding fluid, recheck the fluid level as
described under ªHow to Check.º

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.
Rear Axle
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant. See ªScheduled Maintenance
Servicesº in the Index.
How to Check Lubricant
1500 Series shown, 2500 Series similar

Scheduled Maintenance
7-11
50,000 Miles (83 000 km)

Change automatic transmission fluid and filter 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 at 100,000 miles (166 000 km).
52,500 Miles (87 500 km)
Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking.
Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
60,000 Miles (100 000 km)
If Equipped: Replace passenger compartment air filter. If you drive regularly
under dusty conditions, the filter may require replacement more often.
Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking.
(Continued)
ACTUAL
SERVICED BY:MILEAGE
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE

Scheduled Maintenance
7-14
97,500 Miles (162 500 km)

Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking.

Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
100,000 Miles (166 000 km)

Inspect spark plug wires.
An Emission Control Service.

Replace spark plugs.
An Emission Control Service.

Change automatic transmission fluid and filter 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.
ACTUAL
SERVICED BY:MILEAGE
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE

Scheduled Maintenance
7-15

If you haven't used your vehicle under severe service conditions listed
previously and, therefore, haven't changed your automatic transmission fluid,
change both the fluid and filter.

Inspect Positive Crankcase Ventilation (PCV) valve.
An Emission Control Service.
150,000 Miles (240 000 km)

Drain, flush and refill cooling system (or every 60 months since last service,
whichever occurs first). See ªEngine Coolantº in the Index for what to use.
Inspect hoses. Clean radiator, condenser, pressure cap and neck. Pressure test
the cooling system and pressure cap.
An Emission Control Service.ACTUAL
SERVICED BY:MILEAGE
DATE

7-18
Weatherstrip Lubrication
Silicone grease on weatherstrips will make them last
longer, seal better, and not stick or squeak. Apply
silicone grease with a clean cloth. During very cold,
damp weather more frequent application may be
required. (See ªRecommended Fluids and Lubricantsº
in the Index.)
Automatic Transmission Check
Check the transmission fluid level; add if needed.
See ªAutomatic Transmission Fluidº in the Index.
A fluid loss may indicate a problem. Check the system
and repair if needed.At Least Once a Year
Key Lock Cylinders Service
Lubricate the key lock cylinders with the lubricant
specified in Part D.
Body Lubrication Service
Lubricate all hood latch assembly, secondary latch,
pivots, spring anchor, release pawl, rear compartment
hinges, outer liftgate handle pivot points, rear door
detent link, roller mechanism, liftgate handle pivot
points, latch bolt, fuel door hinge, cargo door hinge,
locks and folding seat hardware. Part D tells you what
to use. More frequent lubrication may be required when
exposed to a corrosive environment.

7-23
Part D: Recommended Fluids
and Lubricants
NOTE: Fluids and lubricants identified below by name,
part number or specification may be obtained from
your dealer.
USAGE
FLUID/LUBRICANT
Engine OilEngine Oil with the American
Petroleum Institute Certified
For Gasoline Engines starburst
symbol of the proper viscosity.
To determine the preferred
viscosity for your vehicle's
engine, see ªEngine Oilº in
the Index.
Engine Coolant50/50 mixture of clean,
drinkable water and use only GM
Goodwrench

DEX-COOL

or Havoline
DEX-COOL

Coolant. See ªEngine Coolantº
in the Index.
USAGEFLUID/LUBRICANT
Hydraulic Brake
SystemDelco Supreme 11
Brake Fluid
(GM Part No. 12377967 or
equivalent DOT
-3 Brake Fluid).
Windshield
Washer SolventGM Optikleen
Washer
Solvent (GM Part No. 1051515)
or equivalent.
Hydraulic Clutch
SystemHydraulic Clutch Fluid
(GM Part No. 12345347 or
equivalent DOT
-3 Brake Fluid).
Power Steering
SystemGM Power Steering Fluid
(GM Part No. 1052884
- 1 pint,
1050017
- 1 quart, or equivalent).
Automatic
TransmissionDEXRON
-III Automatic
Transmission Fluid.
Key Lock
CylindersMulti-Purpose Lubricant,
Superlube
(GM Part
No. 12346241 or equivalent).