The 2017 Mercedes E-Class Estate has been spied undergoing testing in Germany.

Caked in mud, the heavily camouflaged prototype features a two-bar grille, sweptback headlights and a gently sloping roof.  The model also has a tailgate-mounted spoiler, wraparound taillights and an attractive dual exhaust system.

Our spies couldn't get close enough to snap interior photos but the cabin will likely echo the sedan.  This means we can expect an S-Class inspired interior with a flowing dashboard, circular air vents and a large infotainment display.

Specifications are still shrouded in secrecy but the model will ride on the MRA platform and be significantly lighter than its predecessor.  The sedan is expected to lose between 70 - 150 kg (154 - 330 lbs), so expect similar weight savings on the wagon.

Engine options will likely include the usual suspects, so expect to see a variety of familiar four-, six- and eight-cylinder options.