Dodge Challenger SRT Hellcat Owner's Manual page 544

542 MAINTENANCE SCHEDULES
Miles:
Or Months: 6 12 18
Or Kilome-
ters:
Replace the
spark plugs
– 6.4L En-
gine **
Flush and
replace the
engine
coolant at
120 months
if not done
at 150,000
miles
(240,000 km).
** The spark plug change interval is mileage based only,
yearly intervals do not apply.
24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114 120 126 132 138 144 150
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