I wonder how the Porsche Cayenne and VW Touareg get around this "not allowed". There certainly is no egress from the inside via the liftgate in either of those. See here for some photos:

https://mbworld.org/forums/4001972-post9.html

That's because there is no third row to escape from on either of those!

If that is indeed the rationale, why is the option not offered on the ML in the US?? It has no third row from which to escape.

PS - In the other thread, the diagram of the ROW optional external rear mounted spare wheel for the ML is shown.

https://mbworld.org/forums/m-class-w...ting-find.html

I don't know dude, it was discussed on here a coupe of years ago, and someone had an MB source saying this was the case, for the GL at least. Also, don't forget that in Europe, you can order a five-seater GL. Had one as an Airport limo in Prague once.

I was going to buy a Cayanne once, and the rear mounted spare for that was a pretty expensive option, $4,400 IIRC with the wheels I wanted. Importing the kits/offering as an option may not be justified due to demand. Who knows...

You can order a lot of things in the ROW that are not available in the US. MBUSA has their marketing heads firmly planted where the sun never shines,
The Cayenne option is currently US$1525-2075, depending on your wheels.

Still got a an '09 GL320 spare wheel available, if anybody needs one.