I have 10 litres of Castrol Edge 0w30 FST A5/B5 in my shed.

As far as I'm concerned compared to the 5w30 WSS-M2C-913C that my car is designed to have it will have better flow characteristics when the engine is cold and will behave like a standard SAE 30 oil when up to temperature.

It was purchased for my Mondeo as I was running it on 0w30 as it took a while to get upto temperature once the EGR was removed and I fully plan on running my Focus on 0w30 oil once it's out of warranty.

BUT...
Do you think the dealer would see it in the same way I do? My car is due it's first service and I thought I could save some money by supplying the oil.

Or is it not worth the risk while it's under warranty?

 

I would run the recommended oil in a standard engine

 

You do ask some stupid questions

 

I would get some 10w40 mineral in it if you want it to be proper mint.

 

What is stupid?
The oil would cause no harm in my engine. In fact it would be beneficial long term on cold starts.
It also has a higher HTHS compared to the recommended oil for my car.


It's more of a thread about weather it's worth the hassle getting the dealer to use Ł100's worth of oil in my shed.

 

Its a brand new focus, and you are wanting a ford dealer to use the wrong specification oil that you are supplying.. if you ran into problems later on that would be their get out of jail free card regarding warranty claims

 

I wouldn't risk it, it annoyed me in the past to preserve warranty the price the main dealer charged me for oil at service time, but my own fault for buying newish car and a V6 as well.

It was even more galling when I bought the same spec oil at the same Ford dealership's parts department and the lovely parts guys used to do me good deals, sometimes cheaper than going to good old Halfords, now that was a surprise.

 

If it was beneficial it would be used by ford in the first place. Dont be such a tight arse and use the right stuff.