Mercedes-Benz CLS-Class, C257 (EU)

Additional Notes

• The Mercedes-Benz CLS-Class C257 (EU) transfer case fluid capacity is specified as a range of 0.65 to 0.68 liter across all listed 4MATIC variants. A range rather than a fixed value reflects normal manufacturing tolerances in the transfer box housing, meaning the correct fill level is confirmed by the fluid reaching the check plug opening rather than by measuring a precise volume.
• The 0.65-0.68 liter capacity figure applies to a service fill context, meaning fluid added during a routine drain-and-refill procedure on the transfer box unit as installed in the vehicle.
• All five variants share an identical change interval of 125,000 km under normal use conditions. In Mercedes-Benz service terminology, normal use refers to standard on-road driving as opposed to severe or off-road operating conditions.
• The CLS 300 d 4MATIC (257.319), CLS 350 d 4MATIC (257.321), and CLS 400 d 4MATIC (257.323) are diesel-engined variants, while the CLS 350 4MATIC (257.351) and CLS 450 4MATIC (257.359) are petrol-engined variants. Despite the difference in drivetrain character, all five share the same transfer box fluid capacity and service interval specifications.
• The consistent 125,000 km interval across both diesel and petrol 4MATIC configurations from 2018-2023 indicates the transfer box unit itself, rather than engine type, governs the fluid change schedule for the C257 platform.
• The narrow capacity window of 0.65 to 0.68 liter classifies the C257 transfer box as a compact unit. Transfer cases of comparable size are typically single-speed units designed primarily for torque distribution rather than low-range off-road operation, which aligns with the C257 being a road-focused executive coupe.