There have been frequent complaints about the ML BlueTecs not having a spare. In fact, the run flats and lack of a spare prompted me to purchase another marque.

While looking in the EPC for a part number, I discovered that MB does indeed have a rear mounted external spare tire carrier as a factory option - just, in the infinite marketing wisdom of MBUSA, not available in North America. They really are some totally clueless fools!

See the attached parts diagram from the EPC.

So Dutch is there room inside the ML350 Bluetec to put a spare? What do the regular ML350 use as a spare?

This is a company car for me so I had no choice, but I am more concernered about being on a sales call out in the middle of nowhere and a flat without a spare could turn into a 2 day ordeal.

The gassers use a mini spare located under the floor of the cargo area. The AdBlue tank occupies that space in a CDI BlueTec. That's why the rear mounted external spare would be such a nice option.

The external spare is not offered in the US because the US does not allow such a mounting apparently because in the event of rear ending it would potentially smash the rear window. That's why on on both the W164 and W163 that option has not been available. Don't ask me why the G can have it though.

That is strange...Toyota's and Mitsu's have rear mounted spares also. I tend to agree with Dutch, that MBUSA is just totally clueless.

GL Fahrer explained it a while back:

https://mbworld.org/forums/2725865-post10.html

The very early W163's did have that option. I recall seeing it as available when I ordered my first ML in 1998. I believe it also came with heavier rear springs to compensate for the weight of the spare on a long arm to the rear. I can only recall seeing it on one ML over the years. I do not believe the reasoning of not offering it has anything to do with a regulatory issue.

M4 was not offered in the US:

http://www.4x4abc.com/ML320/ml320_M4.html

Both the Porsche Cayenne (see photos) and the VW Touareg offer it as a factory option; and it looks from the MB EPC like it is a very similar method of implementation.

I think it's quite plain and simple - MBUSA has their collective Marketing heads firmly planted in an area where the sun never shines!

That is a super slick setup there....also like the Don't Tread On Me sticker...

I imagine they could also engineer a simple stand up spare option as well to fit in the cargo area....

Beg your pardon but I drove a very early W163 dealer demo for a weeekend before ordering my 98 and the external spare tire mount was installed on this vehicle and it was a factory unit not an aftermarket. I was considering ordering this for my 98 and eventually did not do so. It was also depicted in the US brochures and option sheets. I also know of another that was delivered about the same time as mine that did have this option. I understand that it eventually became not available but some, a very few, did have it. Quite frankly it was a real pain to raise the rear hatch with this carrier.

I vaguely recall that the W163 ML55 AMG came with a full size spare that stood upright INSIDE the cargo compartment because I remember there being a lot of half-hearted complaints about loss of cargo space.

This is correct. It was mounted upright on the left side of the cargo area. As I recall it was also installed flat and some sort of an inflation device was included.

The Jeep Wrangler has an external spare as well.

Have you seen very many of this ROW factory option coming down the line?

I dont see a complete vehicle, just the body and interior. No chassis or anything else but I will say I dont see any out on the yard.

It may be like the Porsche Cayenne. The rear mounted full sized spare is supposed to be the least ordered, i.e. rarest, of the factory options.