OUTLINE
The cooling system uses a pressurized forced circulation system.
The engine water pump assembly is used on the timing chain cover assembly.
A thermostat is located on the water inlet housing to maintain suitable temperature distribution in the cooling system.
Warm water from the cylinder head sub-assembly is sent to the throttle body with motor assembly to prevent throttle body with motor assembly icing (ice buildup). At the same time, warm water from the cylinder head sub-assembly is also sent to the EGR valve assembly to cool it down.
An aluminum radiator core is used for weight reduction.
The engine coolant uses TOYOTA genuine Super Long Life Coolant (SLLC).
| *1 | Return Passage | *2 | EGR Cooler |
| *a | from Heater Radiator Unit Sub-assembly | *b | to Heater Radiator Unit Sub-assembly |
| *c | from Transmission Oil Cooler | *d | from Radiator Assembly |
| *e | from Engine Water Pump Assembly | *f | to Radiator Assembly |
SPECIFICATION
Engine Coolant
TOYOTA genuine Super Long Life Coolant (SLLC) is used. Maintenance interval is as shown in the table below.
SLLC is pre-mixed (50% coolant and 50% deionized water), so no dilution is needed when adding or replacing SLLC in the vehicle.
| Type | TOYOTA Genuine SLLC or the equivalent* | |
| Maintenance Intervals | First Time | 160000 km (100000 miles) |
| Subsequent | Every 80000 km (50000 miles) | |
| Color | Pink | |
Tech Tips
*: Similar high quality ethylene glycol based non-silicate, non-amine, non-nitrite, and non-borate coolant with long-life hybrid organic acid technology. (Coolant with long-life hybrid organic acid technology is a combination of low phosphates and organic acids.)
Thermostat
| Thermostat Opening Temperature | 88°C (190°F) |