Opel ASTRA Owner's Manual page 249

ACEA C3
API SM
API SN resource conserving
Engine oil viscosity grades
Ambient temperature
down to -25 °C
below -25 °C
down to -20 °C
Permitted, but usage of SAE 5W-30 or SAE 5W-40 with dexos quality is recommended.
1)
All countries with international service interval 3 240
All countries with international service interval 3 240
Petrol and diesel engines
SAE 5W-30 or SAE 5W-40
SAE 0W-30 or SAE 0W-40
SAE 10W-30 1) or SAE 10W-40
✔
✔
✔
1)
Technical data 247
✔
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