1998 GMC SAVANA towing

Engine Fan Noise If a Tire Goes Flat
Your vehicle has a clutched engine cooling fan. When the
clutch is engaged,
the fan spins faster to provide more air
to cool the engine. In most everyday driving conditions,
the fan is spinning slower and
the clutch is not fully
engaged. This improves
fuel economy and reduces fan
noise. Under heavy vehicle loading, trailer towing andor
high outside temperatures,
the fan speed increases as the
clutch more fully engages.
So you may hear an increase in
fan noise. This is normal and should not
be mistaken as
the transmission slipping or making extra shifts. It is
merely the cooling system functioning properly. The fan
will slow down when additional cooling
is not required
and the clutch partially disengages.
You may also hear this fan noise when you start
the engine. It will go away as
the fan clutch
partially disengages. It’s unusual
for a tire to “blow out” while you’re driving,
especially if you maintain your tires properly. If air goes
out of a tire, it’s much more likely to leak out slowly.
But
if you should ever have a “blowout,” here are a few
tips about what
to expect and what to do:
If a front tire fails, the flat tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain lane position, and then gently brake
to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you’d use in a
skid. In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the way
you want the vehicle to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake
to a stop -- well off the road if possible.
If a tire goes flat, the next part shows how to use your
jacking equipment to change a flat tire safely.
5-21
ProCarManuals.com

If You’re Stuck: In Sand, Mud, Ice
or
Snow
What you don’t want to do when your vehicle is stuck is
to spin your wheels too fast. The method known as
“rocking” can help you get out when you’re stuck, but
you must use caution.
‘I 1
If you let your tires spin at high speed, they can
explode, and you or others could be injured. And,
the transmission or other parts of the vehicle can
overheat. That could cause an engine
compartment fire
or other damage. When you’re
stuck, spin the wheels
as little as possible. Don’t
spin the wheels above
35 mph ‘(55 kmh) as shown
on the speedometer.
I NOTICE:
Spinning your wheels can destroy parts of your
vehicle
as well as the tires. If you spin the wheels
too fast while shifting your transmission back
and forth, you can destroy your transmission.
For information about using tire chains on your vehicle,
see “Tire Chains” in the Index.
Rocking Your Vehicle To Get It Out
First, turn your steering wheel left and right. That will
clear the area around your front wheels. Then shift back
and forth between REVERSE (R) and a forward gear,
spinning the wheels as little as possible. Release the
accelerator pedal while you shift, and press lightly on
the accelerator pedal when the transmission is in gear.
If
that doesn’t get you out after a few tries, you may need
to be towed out.
If you do need to be towed out, see
“Towing Your Vehicle” in the Index.
5-36
ProCarManuals.com

5. Install a new filter element with the folds in the
down position.
Reverse Steps
1 through 4 to replace the air cleaner.
See “Normal Replacement Parts” for the proper filter
to use.
Refer to the Maintenance Schedule
to determine when to
replace the air filter and crankcase ventilation filter.
See “Scheduled Maintenance Services” in the Index.
I
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
If your vehicle has a diesel engine, see “Automatic
Transmission Fluid” in the Diesel Supplement.
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 GVWR is over 8,600 or
if the vehicle is mainly driven under one or more of
these conditions:
0 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.
6-17
ProCarManuals.com

Maintenance Schedule
I Short TripKity Intervals -- Gasoline Engines I
Every 60,000 Miles (100 000 km): Engine Accessory
Drive Belt Inspection. Fuel Tank, Cap and Lines
Inspection. Exhaust Gas Recirculation System
Inspection. Evaporative Control System Inspection.
Every 100,000 Miles (166 000 km): Spark Plug Wire
Inspection. Spark Plug Replacement. Automatic
Transmission Service (normal conditions). Positive
Crankcase Ventilation (PCV) Valve Inspection.
Every 150,000 Miles (240 000 km): Cooling System
Service (or
every 60 months, whichever occurs first).
These intervals only summarize maintenance services.
Be sure to follow the complete maintenance schedule on
the following pages.
1 Long Wp/Highway Def~tion -- Gasoline Engine
Follow this maintenance schedule only if none of the
conditions from the Short Trip/City Maintenance
Schedule is true.
Do not use this schedule if the vehicle
is used for trailer towing, driven in a dusty area or used
off paved roads. Use the Short Trip/City schedule for
these conditions.
Driving a vehicle with a fully warmed engine
under highway conditions causes engine oil to break
down slower:
7-6
ProCarManuals.com

Short ”kip/City Maintenance Schedule -- Gasoline Engines
The services shown in this schedule up to 100,000 miles
(166
000 km) should be performed after 100,000 miles
(166
000 km) at the same intervals. The services shown
at
150,000 miles (240 000 km) should be performed at
the same interval after
150,000 miles (240 000 km).
See “Owner Checks and Services” and “Periodic
Maintenance Inspections” following.
Footnotes
The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to the
completion of the vehicle’s useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the maintenance
be recorded.
# Lubricate the front suspension, kingpin bushings,
steering linkage and rear driveline center splines.
+ A good time to check your brakes is during tire
rotation. See “Brake System Inspection” under “Periodic
Maintenance Inspections” in Part
C of this schedule.
** Drive axle service (see “Recommended Fluids and
Lubricants” in the Index for proper lubricant to use):
e
e
e
Locking Differential -- Drain fluid and refill at first
engine oil change. At subsequent oil changes, check
fluid level and add fluid as needed.
If driving in
dusty areas
or towing a trailer, drain fluid and refill
every 15,000 miles
(25 000 km).
Standard Differential -- Check fluid level and add
fluid as needed at every oil change.
If driving in
dusty areas or towing a trailer, drain fluid and refill
every
15,000 miles (25 000 km).
More frequent lubrication may be required for
heavy-duty use.
7-8
ProCarManuals.com

I Short TripKity Maintenance Schedule =- Gasoline Engines I
48,000 Miles (80 000 km)
Change engine oil and filter (or every 3 months, whichever occurs first).
An Emission Control Service.
Lubricate chassis components (or every 3 months, whichever occurs first).
(See footnote
#.)
Check axle fluid level and add fluid as needed. (See footnote **.)
Rotate tires. See “Tire Inspection and Rotation’’ in the Index for proper
rotation pattern and additional information. (See footnote
+.)
50,000 Miles (83 000 km)
0 Change automatic transmission fluid and filter if the vehicle’s GVWR is
over
8600 lbs. or if the vehicle is mainly driven under one or more of
DATE I
MILEAGE
DATE
I
~EAGE SERVICED BY: ACTUAL
these conditions: ’
- In heavy city traffic where the outside temperature regularly reaches 90°F
- 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
andfilter
at 100,000 miles (166 000 kin).
(32 O C) or higher.
7-16
ProCarManuals.com

Short TripKity Maintenance Schedule -= Gasoline Engines
100,000 Miles (1 66 000 km) (Continued)
- In hilly or mountainous terrain.
- When doing frequent trailer towing.
- Uses such as found in taxi, police or delivery service.
0 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.
An Emission Control Service.
0 Inspect Positive Crankcase Ventilation (PCV) valve.
150,000 Miles (240 000 km)
Drain, flush and refill cooling system (or every 60 months since last service,
Inspect hoses. Clean radiator, condenser, pressure cap and neck. Pressure test
cooling system and pressure cap.
whichever
occurs first). See “Engine Coolant” in the Index for what to use.
MILEAGE
An Emission Control Service.
7-26
ProCarManuals.com

Long Tripmighway Maintenance ScheduL 3asoline Engines 1
50,000 Miles (83 000 km) (Continued)
- 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)
0 Change engine oil and filter (or every 12 months, whichever occurs first).
0 Lubricate chassis components (or every 12 months, whichever occurs first).
0 Check axle fluid level and add fluid as needed. (See footnote **.)
Rotate tires. See “Tire Inspection and Rotation’’ in the Index for proper
rotation pattern and additional information. (See footnote
+.)
An Emission Control Service.
(See footnote #.)
60,000 Miles (100 000 km)
0 Change engine oil and filter (or every 12 months, whichever occurs first).
0 Lubricate chassis components (or every 12 months, whichever occurs first).
0 Check axle fluid level and add fluid as needed. (See footnote **.)
An Emission Control Service.
(See footnote #.)
DATE I
I MILEAGE
ACTUAL
I SERVICEDBY: I
I DATE I
MILEAGE
0 Clean and repack the front wheel bearings (or at each brake relining,
whichever occurs first).
7-32
ProCarManuals.com