I have an E46 that had the differential oil changed; unfortunately it was
not filled up to the right capacity and now needs to be topped up by about
450ml of extra oil! I do not have the original oil with which it was
initially used (Amsoil SVG 75w90) but have Castrol XO 75W90 (which is
recommended by BMW) with which I am planning to top it up with asap. I have
already done around 400 miles like an idiot and hope this hasn't caused much
Are there any potential issues with combining diff. oil in particular, or
would I be safe to go ahead?