See also:

Opening the DEF filler cap
The filler neck for DEF is behind the fuel filler flap. The fuel filler flap is unlocked or locked automatically when you open or close the vehicle with the SmartKey or with KEYLESSGO. - Swi ...

Vehicle data, GL 550
The data stated here refers specifically to a vehicle with standard equipment. Consult an authorized Mercedes-Benz Center for the data for all vehicle variants and trim levels. ...

Useful information
This Operator's Manual describes all models and all standard and optional equipment of your vehicle available at the time of publication of the Operator's Manual. Country-specific differenc ...