Caterpillar Motor graders

AdBlue (DEF) capacity & service interval

The Caterpillar Motor graders use AdBlue (DEF) fluid with a capacity of 22 liters. Six configurations are covered in the data.

The configuration chart below lists fill volumes and service intervals for each engine and trim variant.

TypeSpecifications
12M series 3, N9F/N9R (2014- )
  • Use: Normal
  • Capacity 22 liter
12M series 3 AWD, N9B/N9P (2014- )
  • Use: Normal
  • Capacity 22 liter
140M Series 3, N9D/N9M (2014- )
  • Use: Normal
  • Capacity 22 liter
140M Series 3 AWD, N9G/N9J (2014- )
  • Use: Normal
  • Capacity 22 liter
160M series 3, N9E/N9L (2014- )
  • Use: Normal
  • Capacity 22 liter
160M series 3 AWD, N9K/N9T (2014- )
  • Use: Normal
  • Capacity 22 liter

Additional Notes

  • All six Series 3 motor grader configurations listed carry a 22-liter AdBlue (DEF) tank capacity, covering the 12M, 140M, and 160M model lines in both standard and all-wheel-drive variants.
  • The 22-liter figure represents the total fluid capacity of the selective catalytic reduction (SCR) tank, which is the reservoir that stores diesel exhaust fluid before injection into the exhaust stream to reduce nitrogen oxide emissions.
  • Caterpillar Motor Graders 12M Series 3 AWD (N9B/N9P) and the standard 12M Series 3 (N9F/N9R) share an identical 22-liter DEF capacity despite the drivetrain difference, indicating the SCR system is not altered between AWD and non-AWD configurations at the 12M level.
  • The same capacity uniformity applies across the 140M Series 3 AWD (N9G/N9J) and 140M Series 3 (N9D/N9M), as well as the 160M Series 3 AWD (N9K/N9T) and 160M Series 3 (N9E/N9L), with all four configurations also rated at 22 liters.
  • Each configuration is designated for normal use conditions, meaning the 22-liter capacity figure applies to standard operating environments rather than severe-duty or extended-cycle service scenarios.
  • All six configurations share a common starting year of 2014, aligning with the broader industry adoption of SCR-based emissions control on heavy construction equipment during that period.
  • The prefix letter groupings in the serial number prefixes, such as N9B/N9P for the 12M AWD and N9F/N9R for the standard 12M, distinguish individual build series within the same model family while the DEF system specification remains constant across all of them.

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