1998 GMC SAVANA trailer

Making Turns
NOTICE:
Making very sharp turns while trailering could cause the trailer to come in contact with the vehicle. Your vehicle could be damaged. Avoid
making very sharp turns while trailering.
When you’re turning with a trailer, make wider turns than
normal.
Do this so your trailer won’t strike soft shoulders,
curbs, road signs, trees or other objects. Avoid jerky or
sudden maneuvers. Signal well
in advance.
Turn Signals When Towing a Trailer
When you tow a trailer, your vehicle has to have extra
wiring and a heavy-duty turn signal flasher (included in
the optional trailering package).
The arrows on your instrument panel will flash
whenever you signal
a turn or lane change. Properly
hooked up, the trailer lamps will also flash, telling other
drivers you’re about
to turn, change lanes or stop. When towing
a trailer,
the arrows on your instrument
panel
will flash for turns even if the bulbs on the trailer
are burned out. Thus, you may think drivers behind
you are seeing your signal when they are not. It’s
important to check occasionally
to be sure the trailer
bulbs are still working.
Driving On Grades
Reduce speed and shift to a lower gear before you start
down a long or steep downgrade. If you don’t shift
down, you might have
to use your brakes so much that
they would get hot and
no longer work well.
On a long uphill grade, shift down and reduce your
speed to around
45 mph (70 km/h) to reduce the
possibility of engine and transmission overheating.
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a lower
temperature than at normal altitudes. If you turn your
engine
off immediately after towing at high altitude on
steep uphill grades, your vehicle may show signs similar to
engine overheating.
To avoid this, let the engine run while
parked (preferably
on level ground) with the automatic
transmission
in PARK (P) for a few minutes before turning
the engine off. If you do get
the overheat warning, see
“Engine Overheating” in
the Index.
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Parking on Hills
You really should not park your vehicle, with a trailer
attached, on a hill. If something goes wrong, your rig
could start to move. People can be injured, and both
your vehicle and the trailer can be damaged.
But if you ever have to park your rig on a hill, here’s
how to do it:
1. Apply your regular brakes, but don’t shift into
PARK
(P) yet. Then turn your wheels into the curb if
facing downhill or into traffic if facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your parking
brake and then shift to
PARK (P).
5. Release the regular brakes.
When You Are Ready to Leave After
Parking
on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
Start your engine;
Shift into a gear; and
Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission fluid (don’t
overfill), engine oil, axle lubricant, belt, cooling system
and brake adjustment. Each of these
is covered in this
manual, and the Index will help you find them quickly.
If you’re trailering, it’s a good idea to review these
sections before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
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Trailer Wiring Harness
The light-duty trailer wiring harness is a six-wire
harness assembly. The optional heavy-duty trailer
wiring package is
an eight-wire harness assembly. The
harness
is stored under the vehicle, along the driver’s
side rear corner
of the frame rail. The heavy-duty trailer
wiring harness has a 30-amp feed wire. Both harnesses
come without connectors and should be wired by a
qualified electrical technician. The technician can use
the following color code chart when connecting the
wiring harness to your trailer.
0 Dark Blue: Use for electric trailer brakes (eight-wire
harness only)
Orange: Trailer accessory (eight-wire harness only)
Light Green: Back-up lamps
0 Brown: Parking lamps
0 Yellow: Left stoplamp and turn signal
0 Dark Green: Right stoplamp and turn signal
0 White (heavy gage): Ground wire
0 White (light gage): Center high-mounted stoplamp
Securely attach the harness to the trailer, then tape or
strap it to your vehicle’s frame rail. Be sure you leave
it
loose enough so the wiring doesn’t bend or break, but
not
so loose that it drags on the ground. Store the
hamess in its original place. Wrap the harness together
and tie it
neatly so it won’t be damaged.
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If No Steam Is Coming From Your Engine
If you get the overheat warning but see or hear no
steam, the problem may not be too serious. Sometimes
the engine can get a little too hot when
you:
0 Climb a long hill on a hot day.
0 Stop after high-speed driving.
0 Idle for long periods in traffic.
0 Tow a trailer. See “Driving on Grades” in the Index.
If
you get the overheat warning with no sign of steam,
try this for a minute or
so:
1. If you have an air conditioner, turn it off.
2. Turn on your heater to full hot at the highest fan
speed and open the window as necessary. If
you no longer
have the overheat warning, you can
drive. Just
to be safe, drive slower for about 10 minutes.
If the warning doesn’t come back on,
you can
drive normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there’s still no sign
of steam, push the accelerator until
the engine speed
is about twice as fast as normal idle
speed. Bring the engine speed back to normal idle speed
after two
or three minutes. Now see if the warning stops.
But then, if
you still have the warning, turn ofSthe
engine
and get everyone out of the vehicle until it
cools down.
You may decide not to lift the hood but to get service
help right away.
3. If you’re in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving
-- DRIVE (D).
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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.
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Removing the Spare Tire and Tools
Your spare tire is stored underneath the rear of your
vehicle.
You will use the ratchet and extension to lower
the spare tire.
A flat rear tire reduces clearance to remove the spare
tire.
If there is less than 12 inches (30.48 cm) between
the ground and the rear bumper or any trailer hitch, jack
up the vehicle until the flat tire is off the ground. (See
“Removing the Flat Tire” and “Installing the Spare
Tire,” Steps
4 through 8, in this section.) Unless your vehicle has
a flat rear tire, do not remove
or restore a tire fromho
a storage position under the
vehicle while the vehicle is supported by a jack. Always
tighten
the tire fully against the underside of the vehicle
when restoring.
If you have a vehicle which was completed from a cab
and chassis, refer to the information from the body
supplierhnstaller.
The spare tire is a
full size tire, like the other tires on
your vehicle.
Remove the retaining wing bolt and lift it off the
mounting bracket. Set the jack and jacking equipment
near the flat tire.
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As shown in the chart, SAE 5W-30 is best for your
vehicle. However, you can use
SAE 1OW-30 if it’s going
to be 0” F (- 18°C) or above. These numbers on an oil
container show its viscosity, or thickness. Do
not use
other viscosity oils, such
as SAE 20W-50.
1 NOTICE:
Use only engine oil with the American Petroleum
Institute Certified For Gasoline Engines
“Starburst” symbol. Failure to use the
recommended oil can result in engine damage
not covered by your warranty.
GM Goodwrench@ oil meets all the requirements for
your vehicle.
If you are in an area where
the temperature falls
below
-20°F (-29”C), consider using either an
SAE 5W-30 synthetic oil or an SAE OW-30 oil. Both
will provide easier cold starting and better protection
for your engine at extremely low temperatures.
Engine Oil Additives
Don’t add anything to your oil. Your dealer is ready to
advise if
you think something should be added.
When to Change Engine Oil
If any one of these is true for you, use the short tripkity
maintenance schedule:
0
0
0
0
0
Most trips are less than 5 to 10 miles (8 to 16 km).
This is particularly important when outside
temperatures are below freezing.
Most trips include extensive idling (such as frequent
driving in stop-and-go traffic).
Most trips are through dusty areas.
You frequently tow a trailer or use a carrier on top of
your vehicle.
The vehicle
is used for delivery service, police, taxi
or other commercial application.
Driving under these conditions causes engine oil to
break down sooner. If any one of these is true for your
vehicle, then you need to change your oil and filter
every
3,000 miles (5 000 km) or 3 months -- whichever
occurs first.
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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.
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