Youre using an oil that is approved by Mercedes, why not just do the b service now and reset the light anyway? Its a waste to only run that decent of an oil for 3 months and then dump it again just to be in line with the cars maintenance schedule, which youre performing early anyway no? Unless is it free maintenance in London?
You also mentioned thinking that you should gain some mileage, which I think the other poster was saying you probably wont see much of a difference in MPG.
Edit: I didnt see your comment about doing the oil yourselves and keeping the reciept, is that for warranty purposes?
Because I am not in the US and we can't just reset the light.
In the UK we have online service history for Mercedes and Smarts. Which can be updated by some independant Garages and Dealers.
Keeping a receipt does nothing over here annoyingly.
The car is a diesel with a DPF doing lots of short trips and idling.
It has sat in a dealer storage for 6 months after being servicing at 1 Year (12k miles).
I want to put in fresh oil but don't want to take it in for the B1 Service over 2 months early.
I never said i would looking to get better fuel economy.
I said my mileage was going to increase and I expect to do 3/4k before the B1.
The usage pattern over the last few months means there will be diesel contamination of the sump.
I would rather spend £60 changing it.
No reason to spend £550/600 on a B1 Service imho as part of that service is brake fluid and it is due only in time having less than 19k on the clock.
Cost saving is not what I prioritise. I want to ensure the engine is as healthy as possible.
Lots of diesels have issues in and around London due to diesel contamination from failed Regens.
At my old work the Ambulances (Sprinters and a mix of 2.7, 2.2 and 3.0 all have 6 week or 3000 mile service intervals) the diesel Response Cars are also DPF afflicted and had many engine failures due to diesel in the oil.
All the Sprinters have DPFs, even the 2003/4/5 2.7's which had them retrofitted at the cost of nearly £15k a time.
If I was doing lots of high speed long runs I would not be doing this interim oil change.
Hopefully that provides some clarification