GMC 2004 Sierra 1500 Pickup Owner's Manual page 543

Additional Required Services (cont'd)
25,000 50,000 75,000 100,000 125,000 150,000
Service (41 500) (83 000) (125 000) (166 000) (207 500) (240 000)
Allison transmission only: Change
automatic transmission fluid and
filter (severe service). See footnote
(m).
Allison transmission only: Change
automatic transmission fluid and
filter (normal service).
Except Allison: Change automatic
transmission fluid and filter (severe
service). See footnote (h).
Except Allison: Change automatic
transmission fluid and filter (normal
service).
Four-wheel drive with automatic
transfer case only: Change transfer
case fluid. See footnote (g).
Inspect evaporative control system.
An Emission Control Service. See
footnotes † and (k).
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