I'm not sure if there are no other coolants on the approved list because Mercedes wants to push their own product or if it's because the coolant manufacturers don't want to pony up the cash to Mercedes to have them test their products. There is a whole lot more motor oil used than coolant, so why doesn't Mercedes sell and recommend their own label oil? There are many approved oils, more for the European market than in the US, but still plenty to choose from.

I'll be interested to hear what the latest word from Zerex is.

Len