BMW 3.0 CS, E9 (USA)

Coolant capacity & service interval

BMW 3.0 CS, E9 (USA) models require 12 liters of coolant. Service intervals include checks every 4000 miles or 6 months and changes every 24 months. The data covers 1 configuration.

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

TypeSpecifications
3.0 CS (1971-1975)
  • Use: Normal
  • Capacity 12 liter
  • Check 4000 miles/ 6 months
  • Change 24 months

Additional Notes

  • The cooling system capacity for the BMW 3.0 CS, E9 (USA) is 12 liters, which represents a full system fill volume encompassing the radiator, engine block passages, heater core circuit, and expansion reservoir.
  • A 12-liter cooling system capacity places this vehicle in a range typical of larger inline-six engines of the early 1970s, where substantial coolant volume was needed to manage heat across a relatively long block.
  • The check interval is specified at every 4,000 miles or 6 months, whichever comes first under normal use conditions, reflecting a schedule where coolant level and concentration are verified without necessarily draining the system.
  • The change interval is set at 24 months under normal use conditions, meaning the full coolant volume of 12 liters is drained and replaced on a time-based cycle rather than a mileage-based one.
  • The separation between the check interval (4,000 miles or 6 months) and the change interval (24 months) indicates that multiple inspections are expected to occur between each full coolant replacement across the 1971-1975 model years.

Other Systems