1999 GMC ENVOY engine

Short Trip/City Scheduled Maintenance
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7-26
100,000 Miles (166 000 km)

Inspect spark plug wires.
An Emission Control Service.

Replace spark plugs.
An Emission Control Service.

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.

Inspect Positive Crankcase Ventilation (PCV) valve.
An Emission Control Service.
150,000 Miles (240 000 km)

Drain, flush and refill cooling system (or every 60 months since last service,
whichever occurs first). See ªEngine Coolantº in the Index for what to use.
Inspect hoses. Clean radiator, condenser, pressure cap and neck. Pressure test
cooling system and pressure cap.
An Emission Control Service.
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ACTUAL
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Long Trip/Highway Scheduled Maintenance
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7-27
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 ªOwner Checks and Servicesº and ªPeriodic
Maintenance Inspectionsº 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, ball joints, steering
linkage, parking brake cable guides, propshaft splines,
universal joints and brake pedal springs.
+ A good time to check your brakes is during tire
rotation. See ªBrake System Inspectionº under ªPeriodic
Maintenance Inspectionsº in Part C of this schedule.
** Drive axle service (see ªRecommended Fluids and
Lubricantsº 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.
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Long Trip/Highway Scheduled Maintenance
yellowblue
7-28
7,500 Miles (12 500 km)
Change engine oil and filter (or every 12 months, whichever occurs first).
An Emission Control Service.
Lubricate chassis components (or every 12 months, whichever occurs first).
(See footnote #.)
Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (See footnote **.)
Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
15,000 Miles (25 000 km)
Change engine oil and filter (or every 12 months, whichever occurs first).
An Emission Control Service.
Lubricate chassis components (or every 12 months, whichever occurs first).
(See footnote #.)
Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (See footnote **.)
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
(32
C) or higher.
± In hilly or mountainous terrain.
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Long Trip/Highway Scheduled Maintenance
yellowblue
7-29
± 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).

Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
22,500 Miles (37 500 km)

Change engine oil and filter (or every 12 months, whichever occurs first).
An Emission Control Service.

Lubricate chassis components (or every 12 months, whichever occurs first).
(See footnote #.)

Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (See footnote **.)

Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
30,000 Miles (50 000 km)

Change engine oil and filter (or every 12 months, whichever occurs first).
An Emission Control Service.
(Continued)
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Long Trip/Highway Scheduled Maintenance
yellowblue
7-31
37,500 Miles (62 500 km)

Change engine oil and filter (or every 12 months, whichever occurs first).
An Emission Control Service.

Lubricate chassis components (or every 12 months, whichever occurs first).
(See footnote #.)

Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (See footnote **.)

Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
45,000 Miles (75 000 km)

Change engine oil and filter (or every 12 months, whichever occurs first).
An Emission Control Service.

Lubricate chassis components (or every 12 months, whichever occurs first).
(See footnote #.)

Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (See footnote **.)

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
(32
C) or higher.
(Continued)
ACTUAL
SERVICED BY:MILEAGE
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ACTUAL
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Long Trip/Highway Scheduled Maintenance
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7-32
45,000 Miles (75 000 km) (Continued)
± 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).

Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
50,000 Miles (83 000 km)

If you haven't used your vehicle under severe conditions listed previously and,
therefore, haven't changed your automatic transmission fluid, change both the
fluid and filter.
52,500 Miles (87 500 km)

Change engine oil and filter (or every 12 months, whichever occurs first).
An Emission Control Service.

Lubricate chassis components (or every 12 months, whichever occurs first).
(See footnote #.)

Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (See footnote **.)

Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
ACTUAL
SERVICED BY:MILEAGE
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE
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Long Trip/Highway Scheduled Maintenance
yellowblue
7-33
60,000 Miles (100 000 km)

Change engine oil and filter (or every 12 months, whichever occurs first).
An Emission Control Service.

Lubricate chassis components (or every 12 months, whichever occurs first).
(See footnote #.)

Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (See footnote **.)

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
(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).
Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
Inspect engine accessory drive belt.
An Emission Control Service.
(Continued)ACTUAL
SERVICED BY:MILEAGE
DATE
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Long Trip/Highway Scheduled Maintenance
yellowblue
7-34
60,000 Miles (100 000 km) (Continued)

Replace fuel filter.
An Emission Control Service. (See footnote
.)
Replace air cleaner filter.
An Emission Control Service.
Inspect fuel tank, cap and lines for damage or leaks. Inspect fuel cap gasket
for any damage. Replace parts as needed.
An Emission Control Service. (See footnote
.)
67,500 Miles (112 500 km)
Change engine oil and filter (or every 12 months, whichever occurs first).
An Emission Control Service.
Lubricate chassis components (or every 12 months, whichever occurs first).
(See footnote #.)
Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (See footnote **.)
Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
75,000 Miles (125 000 km)
Change engine oil and filter (or every 12 months, whichever occurs first).
An Emission Control Service.
ACTUAL
SERVICED BY:MILEAGE
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE
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