BMW 6 series, E24 (USA)

Coolant capacity & service interval

BMW 6 series, E24 (USA) models require coolant with a capacity of 12 liters. The service interval for fluid replacement is 24 months. The data covers 4 configurations.

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

TypeSpecifications
635 CSi (1987-1989)
  • Use: Normal
  • Capacity 12 liter
  • Change 24 months
M6 (1987-1989)
  • Use: Normal
  • Capacity 12 liter
  • Change 24 months
633 CSi (1979-1984)
  • Use: Normal
  • Capacity 12 liter
  • Change 24 months
630 CSi (1976-1979)
  • Use: Normal
  • Capacity 12 liter
  • Change 24 months

Additional Notes

  • All four configurations in the BMW 6 Series E24 (USA) share an identical cooling system capacity of 12 liters, which represents a full system fill volume rather than a partial service top-up.
  • The 630 CSi covers model years 1976-1979, the 633 CSi covers 1979-1984, and both the 635 CSi and M6 share the 1987-1989 range, yet all four carry the same 12-liter capacity figure.
  • A 12-liter cooling system capacity is relatively substantial for a passenger car of this era, reflecting the thermal demands of the inline-six engines used across the E24 lineup.
  • The coolant change interval is specified at 24 months under normal use conditions across every listed configuration, meaning a two-year replacement cycle applies regardless of engine variant or model year.
  • A 24-month coolant service interval is a time-based specification rather than a mileage-based one, so elapsed calendar time governs the replacement schedule rather than distance driven.
  • The M6 (1987-1989), despite housing the high-output S38 engine, carries the same 12-liter capacity and 24-month interval as the standard 635 CSi of the same years, with no differentiation in the cooling system specifications between the two.

Other Systems