The X164 GL-Class debuted at the 2006 North American International Auto Show,[5] and deliveries commenced on September in Europe.

[7] Unlike most three-row luxury SUVs at the time, the GL-Class is based on an elongated and widened version of the M-Class platform, instead of the body-on-frame construction found on vehicles such as the Lexus LX and Cadillac Escalade.

[8] The Guardian said in their review of the GL that "even in places where SUVs are rife, it appears comically out of scale" and described the suspension as "caramel-smooth at pace, but bouncy as a Kiddie Castle on speed bumps" before going on to say "the chrome Mercedes badge on the GL's grille is frying pan-sized and, cutely, right at the height where the head would generally be on a standing four-year-old".

[10] GL-Class models are also optionally available with a tyre pressure monitoring system, DAB digital radio, reversing camera, and rear seat infotainment screens.

[11] Grand Edition models were also offered from 2011, and feature a redesigned front bumper, taller grille with three slats, 20-inch AMG alloy wheels, bi-xenon headlamps, and a two-tone interior.