1999 GMC SIERRA Owner's Manual

Page 385 of 440

GMC SIERRA 1999  Owners Manual Short Trip/City Scheduled Maintenance -- Gasoline Engines
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7-23
Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (S

Page 386 of 440

GMC SIERRA 1999  Owners Manual Short Trip/City Scheduled Maintenance -- Gasoline Engines
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7-24
78,000 Miles (130 000 km)
Change engine oil and filter (or every 3 months, whichever occurs first). 
An Emission Control

Page 387 of 440

GMC SIERRA 1999  Owners Manual Short Trip/City Scheduled Maintenance -- Gasoline Engines
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7-25
Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (S

Page 388 of 440

GMC SIERRA 1999  Owners Manual Short Trip/City Scheduled Maintenance -- Gasoline Engines
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7-26
90,000 Miles (150 000 km) (Continued)
For Two
-Wheel-Drive vehicles only: Clean and repack the front wheel
bearings (or

Page 389 of 440

GMC SIERRA 1999  Owners Manual Short Trip/City Scheduled Maintenance -- Gasoline Engines
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7-27
96,000 Miles (160 000 km)
Change engine oil and filter (or every 3 months, whichever occurs first). 
An Emission Control

Page 390 of 440

GMC SIERRA 1999  Owners Manual Short Trip/City Scheduled Maintenance -- Gasoline Engines
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7-28
100,000 Miles (166 000 km)
Inspect spark plug wires. 
An Emission Control Service.
Replace spark plugs. 
An Emission Co

Page 391 of 440

GMC SIERRA 1999  Owners Manual Short Trip/City Scheduled Maintenance -- Gasoline Engines
yellowblue     
7-29
150,000 Miles (240 000 km)
Drain, flush and refill cooling system (or every 60 months since last service,
whichever occu

Page 392 of 440

GMC SIERRA 1999  Owners Manual Long Trip/Highway Scheduled Maintenance -- Gasoline Engines
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7-30
The services shown in this schedule up to 100,000 miles
(166 000 km) should be performed after 100,000 miles
(166 000 k