1994 GMC SIERRA trailer

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Engine Fan Noise
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 every day
driving conditions
the fan is spinning slower and clutch is not fully engaged.
This improves fuel economy and reduces fan noise. Under heavy vehicle
loading, trailer towing and/or 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.
If a Tire Goes Flat
It’s UfluSual 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, then gently brake to a
stop well
out of the traffic lane.
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Engine Oil Additives
Don’t add anything to your oil. Your GM dealer is ready to advise if you
think something should be added.
When to Change Engine Oil
See if any one of these is true for you:
Most trips are less than 4 miles (6 km).
It’s below freezing outside and most trips are less than 10 miles
(16 km).
The engine is at low speed most of the time (as in door-to-door
delivery, or
in stop-and-go traffic).
You tow a trailer often.
Most trips are through dusty places.
The vehicle is frequently operated off-road.
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 comes
first.
Light Duty Emissions:
If none of them is true, change the oil every 7,500 miles (12 500 km) or
12 months
- whichever comes first. Change the filter at the first oil change
and at every other oil change after that.
Heavy Duty Emissions:
If none of them is true, change the oil every 6,000 miles (10 000 km) or
12 months - whichever comes first. Change the filter at the first oil change
and at every other oil change after that if mileage determines when you
change
your oil. If time determines when you change your oil, change the
filter each time you change your oil.
Engine Coolant Heater (Engine Block Heater)
An engine coolant heater can be a big help if you have to park outside in
very cold weather, 0°F (- 18°C) or colder. If your vehicle has this option,
see “Engine Coolant Heater
” in the Index.
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This doughnut-shaped logo (symbol) is used on most oil containers to help
you select the correct oil.
You should look for this on
the oil container, and use only those oils that
display
the logo.
GM Goodwrench@ oil
(in Canada, GM Engine Oil) meets all the
requirements for your vehicle.
Engine Oil Additives
Don’t add anything to your oil. Your GM dealer is ready to advise if you
think something should be added.
When to Change Engine Oil
See if any one of these is true for you:
0 Most trips are less than 4 miles (6 km).
0 It’s below freezing outside and most trips are less than 10 miles
(16 km).
0 The engine is at low speed most of the time (as in door-to-door
delivery, or in stop-and-go traffic).
0 You tow a trailer often.
0 Most trips are through dusty places.
The vehicle is frequently operated off-road.
If any
of these is true for your vehicle, then you need to change your oil and
filter
every 2,500 miles (4 000 km) or 3 months - whichever comes first.
If
none of them is true, change the oil and filter every 5,000 miles
(8 000 km) or 12 months - whichever comes first.
What to Do with Used Oil
Did you know that used engine oil contains certain elements that may be
unhealthy for
your skin and could even cause cancer‘? Don’t let used oil stay
on your
skin for very long. Clean your skin and nails with soap and water,
or a good hand cleaner. Wash or properly throw away clothing or rags
containing used engine oil. (See the manufacturer’s warnings about the use
and disposal
of oil products.)
Used
oil can be a real threat to the environment. If you change your own oil,
be sure
to drain all free-flowing oil from the filter before disposal. Don’t
ever dispose
of oil by putting it in the trash, pouring it on the ground, into
sewers, or into streams or bodies
of water. Instead, recycle it by taking it to
a place that collects used oil. If you have
a problem properly disposing of
your used
oil, ask your dealer, a service station or a local recycling center
for help.
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I 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, 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).
At high speed for quite a while.
0 In heavy traffic - especially in hot weather.
While pulling a trailer.
IU get the right reading, the fluid should be at normal operating
temperature, which
is 180°F to 200°F (82°C to 93°C).
To check trunsmissioltfluid hot: Get the vehicle warmed up by driving
about
15 miles (24 km) when outside temperatures are above 50°F (1 0°C).
If it’s colder than
50°F (lO”C), drive the vehicle in “D” (3rd Gear) until the
engine temperature gage moves and then remains steady for ten minutes.
Then follow
the hot check procedures.
To check trmzsnzissiorz jZuid 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.
To check the fluid hot or cold
Park your vehicle on a level place.
With the parking brake applied, place the shift lever in “P” (Park).
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 “P’ (Park).
Let the engine run at idle for three minutes or more.
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Trailer Wiring Harness
The optional seven-wire trailer wiring harness is protected by an in-line
fuse
in the battery feed wire. This fuse is near the junction block. See
“Trailer Wiring Harness”
in the Index for more information.
Fuse Block
The fuse block is
behind an access door
at the bottom of the
instrument panel,
next
to the parking brake
release lever.
To remove fuses if you don’t have one, hold the end of the fuse between
your thumb and index finger and pull straight out.
Be, sure to use the correct fuse.
If you ever have a problem on the road and
don’t have a spare fuse, you can “borrow” one of the correct value. Just pick
some feature
of your vehicle that you can get along without-like the radio
or cigarette lighter--and use
its fuse, if it is of the value you need. Replace
it as soon as you can. See “Fuses and Circuit Breakers“ in the Index for
more information.
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Trailering Package
If your vehicle comes with the Trailering Package, there is also a load rating
which includes the weight
of the vehicle and the trailer it tows. This rating
is called the Gross Combination Weight Rating (GCWR).
When you weigh your trailer, be sure
to include the weight of everything
you put
in it. And, remember to figure the weight of the people inside as
part of your load.
Your dealer can help you determine your GCWR.
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After you’ve loaded your vehicle and camper, drive to a weigh station and
weigh
on the front and rear wheels separately. This will tell you the loads on
your axles. The loads
on the front and rear axles shouldn’t be more than
either of the GAWRs. The total
of the axle loads should not be more than
the GVWR.
Open your driver’s door and look at
the CertificatiodTire label to find out
your CWAR and GVWR.
If
you’ve gone over your weight ratings, move or take out some things until
all the weights fall below the ratings. Of course, you should always tie down
any loose items when you load your vehicle or camper.
When you install and load your slide-in camper, check the manufacturer’s
instructions.
If
you want more information on curb weights, cargo weights, cargo weight
rating and the correct center of gravity zone for your vehicle, your dealer
can help
you. Just ask for a copy of “Consumer Information, Truck-Camper
Loading.”
Trailer Recommendations
You must subtract your hitch loads from the CWR for your vehicle. Weigh
your vehicle with
the trailer hitch attached, so that you won’t go over the
GVWR or the GAWR.
You’ll get the best performance if you spread out the weight of your load
the right way, and if‘ you choose the correct hitch and trailer brakes.
For more information, see “Trailer Towing’’
in the Index.
Pickup Conversion To Chassis Cab
General Motors is aware that some vehicle owners may consider having the
pickup box removed and
a commercial or recreational body installed.
Before
you do so, first contact the GM Zone Office for your area for
information on such conversions. (See the “Warranty and Owner
Assistance” booklet for Zone Office.) Owners should be aware that, as
manufactured, there are differences between a chassis cab and a pickup with
the box removed which may affect vehicle safety. The components
necessary to adapt
the pickup to permit its safe use with a specialized body
should be installed by a body builder
in accordance with the information
available from
the Zone Office.
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Selecting the Proper Maintenance Schedule
Here is how to tell which schedule to follow once you find the proper
maintenance chart
to use.
MAINTENANCE SCHEDULE I
Is any one of these true for your vehicle?
Most trips are less than 4 miles (6 kilometers.)
Most trips are less than 10 miles ( 16 kilometers), and the outside
temperatures are below freezing.
The engine is at low speed most of the time (as in door-to-door
delivery, stop-and-go traffic, or commercial use).
You operate in dusty areas or off-road frequently.
You tow a trailer.
If any one (or more) of these is true for your driving, follow Schedule I.
Schedule I is shown by a plus sign (+) on the chart.
MAINTENANCE SCHEDULE I1
Follow Schedule I1 ONLY if none of the above conditions are true.
Schedule
TI is shown by a dot (0) on the chart.
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