[GavinM1984]

First post,

I've put Part Synthetic Castrol GTX 10W40 a3/b4 in my E90 320D.

I know its not the correct oil, I was getting a friend to change the oil and had to buy oil quickly at a nearby supermarket.

I've done over 1000 miles since and the car seems fine, but not sure if its doing long term damage. It said 'for petrol & diesel' cars on the front. Is this damaging the engine?

Is it worth draining the oil and buying a fully synthetic oil and changing the filter again? If so, what oil would you put in?

It's done 80k and it's a 2005 plate.

Thanks

Gavin