Unimog (MB) 403, 406, 413, 416
Coolant capacity & service interval
Unimog (MB) 403, 406, 413, 416 models require coolant with a capacity range of 11 to 24 liters. The service interval for coolant changes is 36 months. The data covers 3 configurations.
The configuration chart below lists fill volumes and service intervals for each engine and trim variant.
| Type | Specifications |
|---|---|
| U 900 (406), U 1100 (416) (1985-1992) |
|
| U 800 (403), U 800L (413) (1970-1992) |
|
| U 900 (406), U 1100 (416) (1970-1992) |
|
Additional Notes
- The U 800 (403) and U 800L (413) share a 24-liter cooling system capacity across the full 1970-1992 production span, a figure that reflects the substantial thermal management demands of heavy-duty utility vehicles in this class.
- The U 900 (406) and U 1100 (416) also carry a 24-liter cooling system capacity for the 1970-1992 period, placing them on equal footing with the 403 and 413 variants in terms of coolant volume.
- A separate 11-liter cooling system specification exists for the U 900 (406) and U 1100 (416) covering the 1985-1992 period, indicating a distinct cooling circuit on certain configurations of those models rather than a replacement of the larger system.
- The difference between 24 liters and 11 liters across the U 900 and U 1100 entries points to two separate cooling circuits or auxiliary systems present on those variants, each with its own service fill requirement.
- All three rows carry a 36-month change interval under normal use conditions, meaning coolant replacement on every configuration listed is tied to a calendar-based schedule rather than a mileage or hours-of-operation threshold.
- A 36-month interval is a standard figure for heavy commercial and utility vehicles of the 1970-1992 era, reflecting the corrosion inhibitor depletion rate of conventional glycol-based coolants rather than a volume-driven consideration.