Nicolla,
Good question. I found castol D2 & 3 ATF fluid. I think I opted for the D3 although having read around the issue a bit albeit after the fact, if you can find Castrol Transmax M that would probably be better. It seems that the D3 may be a little thin (made for the US market and specifically recommended for GM cars), that D2 would be better but that Transmax would be best. That certainly seemed to be the case for the use of these oils in the transmission.
Not much of an answer, but if you need to drive the car I think you should be OK to top up with D2.
JH
