Standard versions of the G63 AMG 6x6 produce 536bhp and 561bhp, which is channelled to all six wheels via an AMG Speedshift Plus 7G-Tronic automatic transmission.
Brabus, however, has boosted that figure to 691bhp and a substantial 708lb ft thanks to the addition of its 'B63S-700' performance kit. The significant gains, of 155bhp and 147lb ft, are thanks to the installation of a pair of new turbochargers, a tweaked ECU, high-flow catalytic convertors, a sports exhaust system and the additional heat shielding for the intake system.
Consequently the six-wheeled 3775kg powerhouse is now capable of sprinting from 0-62mph in 7.4sec, although the top speed remains unchanged at 99mph - an electrical limitation enforced to protect the 37-inch off-road tyres, rather than the powertrain.
The B63S-700 6x6 also features an exhaust valve system that offers 'Sport' and 'Coming Home' modes, allowing for offering 'optimised' power and exhaust noise - or relative silence - when desired.
In order to increase the imposing and purposeful nature of the B63S-700 - not that it really needs any help on that front, mind - Brabus has added a front spoiler, a special grille with an integrated Brabus logo, black xenon headlights, a host of carbonfibre parts and special finishes.
The upgrades continue inside, with a combination of finely-stitched leather and Alcantara. Both the floor and roof lining are finished in leather too, in an effort to deliver a truly top-class feel. Further improvements come in the form of stainless-steel scuff plates with illuminated Brabus logos, special alloy shift paddles and other minor aluminium highlights.
Despite the significant increase in power, a three year, 62,000-mile warranty is standard. Additionally, the B63S-700 package is available for any of Mercedes-Benz's 63 AMG SUVs.
Official pricing has yet to be confirmed for what Brabus describes as "the mightiest G model ever", but the standard model is estimated to cost a not-insignificant £350,000.
To read our full road test of the standard 6x6, click here.
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