2001 GMC SONOMA service

4-33
The exit speed is usually posted.
Reduce your speed according to your speedometer, not
to your sense of motion. After driving for any distance
at higher speeds, you may tend to think you are going
slower than you actually are.
Before Leaving on a Long Trip
Make sure you're ready. Try to be well rested. If you
must start when you're not fresh
-- such as after a day's
work
-- don't plan to make too many miles that first part
of the journey. Wear comfortable clothing and shoes you
can easily drive in.
Is your vehicle ready for a long trip? If you keep it
serviced and maintained, it's ready to go. If it needs
service, have it done before starting out. Of course,
you'll find experienced and able service experts in
GM dealerships all across North America. They'll be
ready and willing to help if you need it.Here are some things you can check before a trip:

Windshield Washer Fluid: Is the reservoir full?
Are all windows clean inside and outside?

Wiper Blades: Are they in good shape?

Fuel, Engine Oil, Other Fluids: Have you checked
all levels?

Lamps: Are they all working? Are the lenses clean?

Tires: They are vitally important to a safe,
trouble-free trip. Is the tread good enough for
long
-distance driving? Are the tires all inflated to the
recommended pressure?

Weather Forecasts: What's the weather outlook
along your route? Should you delay your trip a short
time to avoid a major storm system?

Maps: Do you have up
-to-date maps?

4-34
Highway Hypnosis
Is there actually such a condition as ªhighway
hypnosisº? Or is it just plain falling asleep at
the wheel? Call it highway hypnosis, lack of
awareness, or whatever.
There is something about an easy stretch of road with
the same scenery, along with the hum of the tires on the
road, the drone of the engine, and the rush of the wind
against the vehicle that can make you sleepy. Don't let
it happen to you! If it does, your vehicle can leave the
road in less than a second, and you could crash and
be injured.
What can you do about highway hypnosis? First, be
aware that it can happen.
Then here are some tips:

Make sure your vehicle is well ventilated, with a
comfortably cool interior.

Keep your eyes moving. Scan the road ahead and
to the sides. Check your mirrors and your
instruments frequently.

If you get sleepy, pull off the road into a rest, service
or parking area and take a nap, get some exercise, or
both. For safety, treat drowsiness on the highway as
an emergency.
Hill and Mountain Roads
Driving on steep hills or mountains is different from
driving in flat or rolling terrain.
If you drive regularly in steep country, or if you're
planning to visit there, here are some tips that can make
your trips safer and more enjoyable. See ªOff
-Road
Drivingº in the Index for information about
driving off
-road.

4-39
CAUTION:
Snow can trap exhaust gases under your vehicle.
This can cause deadly CO (carbon monoxide) gas
to get inside. CO could overcome you and kill
you. You can't see it or smell it, so you might not
know it is in your vehicle. Clear away snow from
around the base of your vehicle, especially any
that is blocking your exhaust pipe. And check
around again from time to time to be sure snow
doesn't collect there.
Open a window just a little on the side of the
vehicle that's away from the wind. This will help
keep CO out.
Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little faster
than just idle. That is, push the accelerator slightly. This
uses less fuel for the heat that you get and it keeps the
battery charged. You will need a well
-charged battery to
restart the vehicle, and possibly for signaling later on
with your headlamps. Let the heater run for a while.Then, shut the engine off and close the window almost
all the way to preserve the heat. Start the engine again
and repeat this only when you feel really uncomfortable
from the cold. But do it as little as possible. Preserve the
fuel as long as you can. To help keep warm, you can get
out of the vehicle and do some fairly vigorous exercises
every half hour or so until help comes.
Recreational Vehicle Towing
Your vehicle should not be towed with all four wheels
on the ground. Your transmission has no provision for
internal lubrication while being towed. To properly tow
your vehicle, it should be placed on a platform trailer
with all four wheels off the ground. Towing with all four
wheels on the ground should be avoided.
In rare cases when it's unavoidable and your vehicle
must be towed with all four wheels on the ground, the
propeller shaft to axle yoke orientation should be
marked and the propeller shaft removed following the
applicable service manual removal/installation
procedure. See ªService and Owner Publicationsº in
the Index.

4-46
Towing a Trailer
CAUTION:
If you don't use the correct equipment and drive
properly, you can lose control when you pull a
trailer. For example, if the trailer is too heavy,
the brakes may not work well
-- or even at all.
You and your passengers could be seriously
injured. Pull a trailer only if you have followed
all the steps in this section. Ask your dealer for
advice and information about towing a trailer
with your vehicle.
NOTICE:
Pulling a trailer improperly can damage your
vehicle and result in costly repairs not covered by
your warranty. To pull a trailer correctly, follow
the advice in this part, and see your dealer for
important information about towing a trailer
with your vehicle. Additional rear axle
maintenance is required for a vehicle used to tow
a trailer. See ªScheduled Maintenance Servicesº
in the Index.
Your vehicle may be able to tow a trailer. To identify
what the vehicle trailering capacity is for your vehicle,
you should read the information in ªWeight of the
Trailerº that appears later in this section.
If yours was built with trailering options, as many are,
it's ready for heavier trailers. But trailering is different
than just driving your vehicle by itself. Trailering means
changes in handling, durability and fuel economy.
Successful, safe trailering takes correct equipment, and
it has to be used properly.

4-49
Vehicle*Axle
Ratio Max. Trailer Wt.
4WD Regular Cab
4.3L V6/Manual Trans. 3.42 4,200 lbs. (1 907 kg)
4.3L V6/Auto. Trans. 3.42
3.735,700 lbs. (2 588 kg)
5,700 lbs. (2 588 kg)
4WD Extended Cab
4.3L V6/Manual Trans. 3.42 4,000 lbs. (1 816 kg)
4.3L V6/Manual Trans.
w/ZR23.73 4,400 lbs. (1 998 kg)
4.3L V6/Auto. Trans. 3.42
3.735,500 lbs. (2 497 kg)
5,500 lbs. (2 497 kg)
4.3L V6/Auto. Trans.
w/ZR23.73 4,900 lbs. (2 225 kg)
4WD Crew Cab
4.3L V6/Auto. Trans. 3.42
3.735,200 lbs. (2 361 kg)
5,200 lbs. (2 361 kg)* If your vehicle is equipped with RPO V4A
(Xtreme
Sport Appearance Package), your vehicle
can tow a maximum of 800 lbs. (363 kg). For more
information on RPO codes, see ªService Parts
Identification Labelº in the Index.
#If your vehicle is equipped with a code 5 engine you
must use regular unleaded gasoline rated at 87 octane or
higher when towing.
Maximum trailer weight is calculated assuming the
driver and one passenger are in the tow vehicle and it
has all the required trailering equipment. The weight of
additional optional equipment, passengers and cargo in
the tow vehicle must be subtracted from the maximum
trailer weight. The weight of the trailer tongue also
affects trailering capacity. See ªWeight of the Trailer
Tongueº later in this section.
You can ask your dealer for our trailering information or
advice, or you can write us at the address listed in your
Warranty and Owner Assistance Information Booklet.
In Canada, write to:
General Motors of Canada Limited
Customer Communication Centre, 163
-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7

4-55 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 system. 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.

5-6
8. Now connect the
black negative (
-)
cable to the
good battery's
negative (
-) terminal.
Don't let the other end touch anything until the next
step. The other end of the negative cable doesn't go
to the dead battery. It goes to a heavy, unpainted
metal part on the engine of the vehicle with the
dead battery.9. Attach the cable at least 18 inches (45 cm) away
from the dead battery, but not near engine parts that
move. The electrical connection is just as good
there, but the chance of sparks getting back to the
battery is much less.
10. Now start the vehicle with the good battery and run
the engine for awhile.
11. Try to start the vehicle with the dead battery. If it
won't start after a few tries, make sure all
connections are good. If it still won't start, it
probably needs service.
12. Use the following procedure to remove the jumper
cables. Take care that they don't touch each other or
any other metal.

5-7
Jumper Cable Removal
A. Heavy, Unpainted Metal Engine Part
B. Good Battery
C. Dead BatteryTo disconnect the jumper cables from both vehicles, do
the following procedure:
1. Disconnect the black negative (
-) cable from the
heavy, unpainted metal engine part on the vehicle
that had the dead battery.
2. Disconnect the black negative (
-) cable from
the negative (
-) terminal on the vehicle with the
good battery.
3. Disconnect the red positive (+) cable from
the vehicle with the good battery.
4. Disconnect the red positive (+) cable from the
other vehicle.
Towing Your Vehicle
Consult your dealer or a professional towing service if
you need to have your vehicle towed. See ªRoadside
Assistanceº and ªRecreational Vehicle Towingº in
the Index.