AO Platinum Member
Join Date: Feb 2002
Location: The land that Time forgot
I've always used Selenia 20k (formerly known as "Formula Alfa Romeo").
It's semi-synthetic 10W40 and lasts for the 12,000 miles (20k kms) in between the service intervals, though it gets a bit thinner after 6-8000, so I now tend tdo an "in-between services" oil change at 6000 miles.
A few people go for 5W... and .../50 grades in various combinations but your lad just doesn't need it and there's the prospect of damaging the engine if you run too-thin or too-thick oil. Mr Romeo says 10W40 for the UK, all year round and there's no point trying to second-guess him, I reckon.
I find the 2.0 TS engine does like a drop of oil, so you must check it every week and just top it up again. I tend to use about 1.5 litres in between the oil changes at 6000. Selenia handily comes in a 2ltr tin.
Elsewhere on this forum, people have suggested that low or old oil can contribute to the famous cam variator problem, so that should help you remember to keep the level topped up and the oil as fresh as you can afford.
Anyway, good luck with you GTV.
No bullets for Chaingun..