JLG 1850SJ Operation And Safety Manual page 172

SECTION 7 - GENERAL SPECIFICATIONS & OPERATOR MAINTENANCE
17. DEF Supply Module Filter (If Equipped) 18. Optional Fuel Filter/Water Separator
Lube Point(s) - Replaceable Element
Interval - Drain water daily; Change every year or 600 hours of
operation
Interval - 500 hours or 2 years, whichever comes first
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