towing GMC ENVOY 1998 Owner's Manual

NOTICE:
Do not tow with sling-type equipment or rear
bumper valance damage will occur.
Use wheel-lift
or car-carrier equipment. Additional ramping
may be required for car-carrier equipment. Use
safety chains and wheel straps.
Towing a vehicle over rough surfaces could
damage a vehicle. Damage can occur from
vehicle to ground or vehicle to wheel-lift
equipment. To help avoid damage, install a
towing dolly and raise the vehicle until adequate
clearance is obtained between the ground and/or
wheel-lift equipment.
Do not attach winch cables or J-hooks to
suspension components when using car-carrier
equipment. Always use T-hooks inserted in
the T-hook slots.
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Engine Fan Noise
This 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 clutch is
not engaged. This improves fuel economy and
reduces
fan noise. Under heavy vehicle loading, trailer
towing and/or high outside temperatures, the fan speed
increases when the clutch 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 disengages.
You may
also hear this fan noise when you start the
engine. It will go away
as the fan clutch disengages.
If a Tire Goes Flat
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
iacking equipment to change
a flat tire safely. u Y a. c
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Removing the Spare Tire and Tools
The jacking equipment you’ll need is stored along the
driver’s side inner rear quarter panel. Your vehicle is
also equipped with work gloves and a plastic ground
mat to assist in the changing
of a flat tire.
To remove your jack
cover, pull up on the latches
on the cover. Remove the
wheel blocks, jack and
wheel wrench.
NOTICE:
Never remove or restow a tire frodto a stowage
position under the vehicle while the vehicle is
supported by a jack. Always tighten the tire
fully against the underside of the vehicle
when restowing.
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Rocking Your Vehicle To Get It Out
First, turn your steering wheel left and right. That will
clear
the area around your front wheels. Shift the transfer
case into
4HI. 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. Or, you can use
your recovery
hooks. If you do need to be towed out, see
“Towing Your Vehicle”
in the Index.
Using the Recovery Hooks
Your vehicle is equipped with recovery hooks. The
recovery hooks are provided at the front
of your vehicle.
You may need
to use them if you’re stuck off-road
and need
to be pulled to some place where you can
continue driving.
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A CAUTION:
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
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
15,000 miles
(25 000 km) if the vehicle is mainly driven under one
or more of these conditions:
In heavy city traffic where the outside temperature
regularly reaches
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 every
50,000 miles (83 000 km).
See “Scheduled Maintenance Services’’ in the Index.
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Maintenance Schedule
I Short Trip/City Intervals I
Every 150,000 Miles (240 000 km): Cooling System
These intervals only summarize maintenance services.
Be sure to follow the complete maintenance schedule on
the following pages. Service
(or every
60 months, whichever occurs first).
1 Long TridHiEhwav Definition
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 TripKity schedule for
these conditions.
Driving a vehicle with a fully warmed engine under
highway conditions causes engine oil
to break
down slower:
Long TridHiehwav Intervals
Every 7,500 Miles (12 500 km): Engine Oil and Filter
Change (or every 12 months, whichever occurs first).
Chassis Lubrication (or every 12 months, whichever
occurs first). Drive Axle Service. Tire Rotation.
Every 15,000 Miles (25 000 km): Automatic
Transmission Service (severe conditions only).
Every 30,000 Miles (50 000 km): Fuel Filter
Replacement. Air Cleaner Filter Replacement.
Every 50,000 Miles (83 000 km): Automatic
Transmission Service (normal conditions).
Every 60,000 Miles (100 000 km): Engine
Accessory Drive Belt Inspection. Fuel Tank, Cap and
Lines Inspection.
Inspection. Spark Plug Replacement. 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.
Every 100,000 Miles (166 000 km): Spark Plug Wire
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Short TripKity Maintenance Schedule I
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 ktn).
See “Owner Checks and Services” and “Periodic
Maintenance Inspections” following.
Footnotes
7 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 ~1sefu1 life. We, however.
urge that all recommended maintenance services be
performed
at the indicated intervals and the maintenance
be recorded.
## Lubricate the front suspension, ball joints, steering
linkage, parking brake cable guides, propshaft splines.
universal joints and brake pedal springs.
+ A ~ood 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):
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
hea\jy-duty
or off-l-oad use.
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1 Short TripKity Maintenance Schedule I
27,000 Miles (45 000 kin) (Continued)
0 Lubricate chassis components (or every 3 months, whichever occurs first).
0 Check readfront axle fluid level and add fluid as needed. Check constant
(See footnote
#.)
velocity
joints and axle seals for leaking. (See footnote **.)
30,000 Miles (50 000 km)
0
0
0
0
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 readfront axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (See footnote
**.)
Replace fuel filter.
An Emission Control Service. (See footnote?.)
Replace air cleaner filter.
An Emission Control Service.
Change automatic transmission fluid and filter if the vehicle is mainly driven
under one or more of these conditions:
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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.
I i
DATE I
I MILEAGE ACTUAL I SERVICEDBY: I
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Short TripKity Maintenance Schedule
0 Check readfront axle fluid level and add fluid as needed. Check constant
0 Change automatic transmission fluid and filter if the vehicle is mainly driven
velocity
joints and axle seals for leaking. (See footnote
**.)
under one or more of these conditions:
- In heavy city traffic where the outside temperature regularly reaches 90°F
- In hilly or mountainous terrain.
(32 "C) or higher.
- When doing frequent trailer towing.
- Uses such as found in taxi, police or delivery service.
If you do nut use your vehicle under any of these conditions, change the fluid
and filter every 50,000 miles (83 000 km).
Inspect air cleaner filter if you are driving in dusty conditions. Replace filter
if necessary.
An Emission Control Service. (See footnote?.)
48,000 Miles (80 000 km)
0 Change engine oil and filter (or every 3 months, whichever occurs first).
Lubricate chassis components (or every 3 months, whichever occurs first).
An Emissiorz Control Service.
(See footnote
#.)
DATE I
(Continued)
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I Short Trip/City Maintenance Schedule 1
60,000 Miles (100 000 km) (Continued)
0 Lubricate chassis components (or every 3 months, whichever occurs first).
(See footnote
#.)
Check readfront axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (See footnote
**.)
0 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
- In hilly or mountainous terrain.
(32°C)
or higher.
- When doing frequent trailer towing.
- Uses such as found in taxi, police or delivery service.
Ifyou do not use your vehicle under any of these conditions, change the fluid
and filter every
50,000 miles (83 000 km).
An Emission Control Service.
Art Emission Control Service. (See footnote?.)
An Emission Control Service.
0 Inspect engine accessory drive belt.
0 Replace fuel filter.
0 Replace air cleaner filter.
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