I only make that a difference of 0.4 litres and the filter will hold that much. I would have thought the level should be on the max mark.

I've just bought a draper slimline oil drain pan so I did an oil change on my deisel bmw yesturday. I let it drip for ages but when I refilled with oil the castrol website specifys 6.7 litres of oil yet I've poured in 6.4 litres and the level is now in the middle of the marker on the dipstick.

Should I put the remaining 3 litres in?

JJ

Last time I did sums, 6.7-6.4 = 0.3litres not 3 litres..

Have you changed the filter and refilled it with oil before replacing?

Correct oil level is Max..