The Kubota GL21 coolant capacity is listed as 1.66 gal (6.3 L). It also lists coolant type ethylene glycol-based coolant and ASTM D3306 compatible and antifreeze mix 50/50 coolant and distilled water mix.
Kubota GL21 Coolant Capacity
| Coolant capacity | 1.59 gal (6 L) |
|---|---|
| Cooling system capacity | 1.66 gal (6.3 L) |
| Radiator capacity | 1.59 gal (6 L) |
| Coolant type | ethylene glycol-based coolant and ASTM D3306 compatible |
| Antifreeze mix | 50/50 coolant and distilled water mix |
| Engine model | D1403 |
| Engine horsepower | 20.7 hp (15.4 kW) |
| Engine displacement | 1.4 L (85.4 cu in) |
Coolant Capacity Comparison Chart
Coolant capacity comparison
Engine horsepower comparison
Engine displacement comparison
Kubota GL21 Coolant and Engine Notes
| Coolant capacity note | The Kubota GL21’s key coolant figure here is 1.66 gal (6.3 L) for cooling system capacity. Use that before buying coolant or draining the system |
|---|---|
| Radiator capacity note | Radiator capacity is listed as 1.59 gal (6 L). The full cooling system can be higher because coolant also sits in the engine and hoses |
| Coolant type note | Use the right coolant formula for the Kubota GL21: ethylene glycol-based coolant and ASTM D3306 compatible. Cheap wrong coolant is not a smart saving if it causes corrosion or deposits |
| Antifreeze mix note | The 50/50 coolant and distilled water mix mix gives the Kubota GL21 coolant system a sensible balance of freeze protection, boil protection and corrosion protection |
| Engine context note | The Kubota GL21 engine data captured here is engine model D1403, engine horsepower 20.7 hp (15.4 kW), and displacement 1.4 L (85.4 cu in). Bigger engines usually need more coolant and more careful refill bleeding |
| Refill note | Coolant changes are simple but easy to do sloppily. On the Kubota GL21, plan around 1.66 gal (6.3 L) and confirm the final level after air works out of the system |
Kubota GL21 Coolant Capacity FAQ
How much coolant does the Kubota GL21 take?
The main coolant amount captured for the Kubota GL21 is 1.66 gal (6.3 L). Buy a little extra so you can top up after the engine warms up and cools down.
Does coolant type matter on the Kubota GL21?
Yes. Capacity tells you how much to buy; coolant type tells you what to buy. For the Kubota GL21, the captured coolant type is ethylene glycol-based coolant and ASTM D3306 compatible.
What antifreeze mix does the Kubota GL21 use?
The captured antifreeze mix for the Kubota GL21 is 50/50 coolant and distilled water mix. A 50/50-style mix is the common practical answer unless your manual or climate calls for something different.
When should the Kubota GL21 coolant be replaced?
Use the service interval in the operator manual as the service guide. Coolant can look okay but still lose corrosion protection over time.
Why does the Kubota GL21 coolant amount differ from other models?
Coolant capacity changes with engine and radiator setup. For the Kubota GL21, the supporting engine data is engine model D1403, horsepower 20.7 hp (15.4 kW), and displacement 1.4 L (85.4 cu in).
Mistakes do happen. Tractor coolant specs can change by year, market, engine, radiator, cab/heater setup and service procedure. Please check the operator manual, decal information and official kubotausa.com website for official information before draining or refilling the cooling system.
