Oil question

[Pedrocious]

Hi all.
I just bought 8 litres of 15-40 Castrol gtx modern engine as it was on sale. I've about 3 litres of Castrol gtx diesel remaining from a previous change. Is it advisable/acceptable to mix these two types of oil for my next change?
Thanks.

[Yorkshire Devil]

Hi all.
I just bought 8 litres of 15-40 Castrol gtx modern engine as it was on sale. I've about 3 litres of Castrol gtx diesel remaining from a previous change. Is it advisable/acceptable to mix these two types of oil for my next change?
Thanks.

Shouldn't make a sh!t of difference. I've mixed all sorts

[the silver surfer]

Personally I'd never mix two different brands of oil, but maybe it actually makes zero difference to the engine running, just a personal preference I guess.

[marcdtr]

Should be fine mate

[Loobs]

It will make no difference at all.