However, something else that I discovered relates to what I noted in the first messsage. Here in the USA, all the M-class brochures, for both the 320 and the 430, list 5,000 lbs as their towing limit. Yet at the corporate website, it lists 7,418 lbs for both engine models. [in all cases, trailer brakes are assumed]

Apparently, MB derates towing capacities for the USA, so far for the M-class, by as much as one-third!

[But why? Could it be this country's penchant for lawsuits? It has long been rumored that MB withheld ABS in USA cars for a decade because they waited until they were convinced that it presented no liability questions -- i.e., it was adequately trustworthy.]
In any case, this derating is disturbing. It can well be that the GWagen's towing capacity will be similarly derated (from fear of litigation?) from our coveted 7700 lbs to a mere 5,200 lbs. This would be bad, not only from the standpoint of warranty coverage, but also legal liability and insurance coverage in the event of an accident, if we violated this USA decree in favor of the international ratings.

Let's hope that they don't derate the G -- we'll have to wait and see the official USA brochures to find out!