French forum Worldscoop has published a series of brochure photos of the new model.
Although no images of the interior have surfaced yet, the GLS is likely to adopt the redesigned dash facia from the GLE, with a floating infotainment screen and reprofiled ventilation outlets.
Likewise, engines will be borrowed from the GLE range as well. Currently the Australian line-up features GL350 CDI, GL500 and GL63 AMG.
After the update expect to see GLS350 d, with a 190kW/620Nm V6 diesel, as well as pair of petrol V8s, the GLS500 and the more powerful Mercedes-AMG GLS63 S, which should arrive with the same 430kW/760Nm twin turbo V8 as the GLE63 S.
After making an official debut at the Los Angeles Auto Show, the GLS should arrive on Australian soil early next year.