2026-07-21 · 4 min read
Toyota Sienta Coolant Guide Malaysia
Sienta hybrid has engine coolant plus a separate inverter cooling loop. Never mix them — first change at 5 years from new.

Toyota SLLC (pink OAT) — change every 4 years or 60,000 km. NHP170 hybrid has dual cooling circuits (engine + inverter). NCP175 petrol has single circuit. Check level every 10,000 km as 1NZ engines can develop minor coolant leaks at higher mileage.
Coolant Service
- NCP175 coolant flush: RM 100–160
- NHP170 dual circuit flush: RM 180–280 — do both circuits together
