E39 525 Gear oil and diff oil??

Ok regarding my e39 everything pretty much is up to date and fresh but on my cars i like to refresh the diff oil and autobox oil, i know there is many debates regrding the gear oil and its lifetime etc, My indy who is BMW specialist recommends doing them now firstly where and which is the correct oils for the diff and autobox?
i was considering getting a auto box specialst do to the oil so its properly drained out and flushed and a new filter fitted and correct oil, also would you recommend me doing the power steering fluid also ? thanks any advice appreciated

Diff 75w90 iirc no idea on the auto box

was researching this grade and it is indeed 75w90 i need, i knoiw opie oils stock it ut does anyone know where in ireland it can be bought ?

I have to recommend castrol syntrax gearoil 75/90. I stuck it in my BMW 1150 gs and it made a huge difference to shifting performance

@[claudio] are you sure? The manuals are a very specific oil.

dave
I'm referring to diff oil 75w90
regarding the auto box I think it's dexion 3

I did the diff oil a while back, it stinks! Probably about time to go again.

+1 that oil wreaks [emoji1]

Claudio b&q sell it and id say halfords too

Halford online say only their own brand
I dint fancy using cheap stuff
would prefer castrol tbh

Castrol syntrax in b&q liffey valley last time i was there you need 1.25 ltrs so 2 bottles

Thanks for the help
once I know it's 75 90 as I wasn't 100 per cent sure
cheers