Mack Mack Differentials

Differential fluid capacity & service interval

Mack Differentials require differential fluid with a capacity range of 34 to 36 liters. Service intervals include 64000 km, 128000 km, 400000 km, and 800000 km. The data covers 4 configurations.

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

TypeSpecifications
Differential S 34R
  • Use: Vocational
  • Capacity 34-36 liter
  • Change 64000 km/ 12 months/ 1200 hours
  • Code: Mack S 34R
Differential S 34R
  • Use: Vocational, extended
  • Capacity 34-36 liter
  • Change 128000 km/ 12 months/ 1200 hours
  • Code: Mack S 34R
Differential S 34R
  • Use: Highway use
  • Capacity 34-36 liter
  • Change 400000 km/ 24 months
  • Code: Mack S 34R
Differential S 34R
  • Use: Highway use, extended
  • Capacity 34-36 liter
  • Change 800000 km/ 36 months
  • Code: Mack S 34R

Additional Notes

  • The Mack Differentials S 34R carries a fluid capacity of 34-36 liters, a range that reflects normal fill variation rather than a distinction between service fill and overhaul quantities.
  • Under vocational use conditions, the S 34R differential fluid change interval is set at 64,000 km, 12 months, or 1,200 hours, whichever comes first.
  • The vocational extended interval doubles the standard vocational distance threshold to 128,000 km, while retaining the same 12-month and 1,200-hour limits.
  • Highway use conditions carry a significantly longer distance-based interval of 400,000 km, paired with a 24-month time limit, reflecting the less demanding thermal and load cycles associated with on-highway operation.
  • The highway use extended interval reaches 800,000 km and extends the time limit to 36 months, the longest interval specified across all four S 34R configurations.
  • The fluid capacity of 34-36 liters remains constant across all four use conditions for the S 34R, meaning the operating environment affects only the change interval, not the fill volume.