Hummer H1 (USA / CAN)
Coolant capacity & service interval
Hummer H1 (USA / CAN) coolant capacity is 25 liter. Service intervals include normal use. The data covers 2 configurations.
The configuration chart below lists fill volumes and service intervals for each engine and trim variant.
| Type | Specifications |
|---|---|
| H1 6.5TD (1996-2004) |
|
| H1 6.5D (1994-2004) |
|
Additional Notes
- The Hummer H1 cooling system holds 25 liters of coolant, a notably large capacity that reflects the thermal demands of a heavy-duty diesel powertrain in a vehicle of substantial size and weight.
- Both the naturally aspirated 6.5D and the turbocharged 6.5TD configurations share an identical 25-liter cooling system capacity, meaning the addition of a turbocharger on the 6.5TD did not alter the coolant volume requirement.
- The 25-liter figure applies to a normal use condition, which in coolant service contexts generally refers to standard on-road driving cycles rather than sustained extreme-load or off-road operation.
- The 6.5D configuration covers model years 1994-2004, while the 6.5TD entered the specification range starting in 1996, giving the turbocharged variant a two-year-shorter overall span within the same generation.
- A 25-liter cooling system capacity is considerably larger than what is found in most passenger cars, where coolant capacities typically fall in the 6-10 liter range, underscoring the scale of the H1 engine bay and its associated cooling infrastructure.