Honda GOLDWING GL1800/A 2015 Owner's Manual page 184

Add Engine Oil:
12. Fill the crankcase with the recommended oil
3.9 US qt (3.7 )
13. Install the oil fill cap/dipstick securely.
14. Start the engine and let it idle for 3 – 5 minutes.
15. Stop the engine and wait 2 – 3 minutes.
16. Check that the oil level is at upper level mark on the dipstick
17. Check that there are no oil leaks.
If a torque wrench is not used for installation, see your dealer as soon as
possible to verify proper assembly.
Engine Oil & Filter
(page 176), approximately:
Servicing Your Honda
(page 178).
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