Weird Mercedes Gls, E-class Wagon Prototypes Spotted

We've been seeing some strange things recently from Mercedes-Benz. A few days ago spy photographers happened upon the SLS AMG E-Cell lapping the Nürburgring with a gaggle of cameras and sensors mounted all over it. Now, Mercedes-Benz Prototypes on YouTube has posted up a video showing both a GLS-Class and E-Class wagons with some very strange bits in plain view.

We start with the GL500 and it's, well, round-ish thing mounted where the rear glass would be. We can't see anything inside the suv, and to be honest we have no clue whatsoever about the larger bits sticking out from where the window should be. The small item lowest and furthest forward, however, appears to be some vent or nipple where a hose might attach.

That's not to say we're completely in the dark here. You'll notice a black taped-off area on the rear fascia. That looks suspiciously like a hydrogen fill point for a fuel cell, and we know Mercedes is quite deep in fuel cell testing. Just a couple months ago the automaker unveiled its pre-production GLC F-Cell, a fuel-cell powered hybrid crossover. It's certainly likely this vehicle is part of the fuel cell testing fleet.

The E-Class wagon is a bit more of a mystery to us. Again, the large protrusion with the oval-shaped black section makes us think fuel cell, as there is similarity to the hydrogen ports we've seen on the F-Cell. Hydrogen is kept under much greater pressure than gasoline or diesel fuel, which is why special ports are required establish a firm connection when filling up. Could we be looking at prototype or pre-production hybrid fuel cell variants of the E-Class wagon?