Great app I found

[MercedesDriver]

Recently I had discussion with salesman about recommended engine oil for my W215 and he insisted that I should use only 5W-30 full synthetic oil, until I showed him what is recommended by this app. I find it very helpful.
http://play.google.com/store/apps/details?id=com.shell.sitibv.lubematch

 

[V12]

I'd rather use the official MB handbook as a reference rather than an App by a 3rd party.

 

[markjay]

The engine oil viscosity table is pretty standard and not manufacturer-specific.

For UK temperatures it is either 0w or 5w on the winter end, and either 30 or 40 on the other.

In that sense neither Shell nor MB (nor the dealer) have any particular knowledge above what is showing in the standard API table.

As for the rest.... whatever meets the relevant MB spec sheet.

On another note, my experience with Service Advisors is that they are not very technical at all and usually have no idea what type of oil is recommended for your car or even what type of oil their own garage is using. So I would not read too much into what the Service Advisor says..