ALFAGTV6.COM

I am about to change the transmission fluid, but I can not find any information how many liters should be used and what is the recommended type ...

your help as always will be appriciated

badger77 Some may find my recommendation strange but I have tried a wide variety of gear oils in my GTV6 - including synthetics and have settled on cheap and nasty Motomaster 80W90 from Canadian tire.it is identified as "extreme pressure" and contains NO limited slip additives - very important.As stated I've tried many types both on the street and the track and have been most satisfied with this stuff.You need just shy of 3 litres for a fill.

75W90, which I think is synthetic based, and as he ^^ said about 3 litres quantity, or fill it up until the fluid pours back out.

Hi Murray, if I understand correctly, you write that it is better an oil without additives for LSD. May I ask why? They worsen the synchros performances? Are you using the same oil for your LSD alfa 75 twin spark?
I ask you that because a few time ago I had the transaxle of my car rebuilt (I also wrote a post referring to LSD clutches correct assembly procedure). According to my small experience, when you use a non LSD oil in a LS differential, a noise is heard (I would say similar to the one of a wheel on wet asphalt) when you drive the car on a curve. On my car I shifted to Castrol Hypoy LS90, and the noise has completely gone. Should an oil like that be used only on LSD cars?
Thanks
Oscar

Oscar no that is not what I intended to suggest.I was referring strictly to the non LSD GTV6 box.The TS box requires the limited slip additive to work correctly as you stated.Overall I found the TS box to be much better and less touchy about oil grades and types than the GTV6 but it does require a LS additive.

LS trans oil helps non LS boxes to perform better friction modifier helps synchro to work better ... old alfa style synchros need more friction to work properly ... new non lsd synthetics are too slipery, box feels good shifts are nice and soft but still grinding . with LS oil you actualy feel how hub grab syncro ring (cant explain the feel)

Which one to choose out of Castrol, Motul or something similiar that could be easier to find on market?

LS modifiers are engineered to make the break-away friction the same as when sliding, this is done to get rid of the shudder/knocking sounds when there is a speed difference over the diff.
It's not more slippery or less slippery, it's slippery in a different way.