On Alfa number 15
AO Platinum Member
Join Date: Dec 2005
Location: United Kingdom
I read somewhere that the only difference between a 0w and a 5w rated oil is that the pour point is a lower temperature. The actualy viscosity is the same despite the rating being lower.
I have used 5w-40 in all of my TS cars without any problems, and they run quieter and smoother than on 10w-40 semi synthetic, so if the first sentence is true the same would apply to the 0w-40
Also an oil is never thinner when cold than when hot, so as long as the 40 Hot rating is the same, it can never be too thin.
I would also change the oil more often than the 12,000 miles that the book says. It is far too long, 6000-9000 miles is a better bet IMO.
One of my cars had been run on selenia and had the oil changed every 12,000 miles. The cam area was coated in a black varnish like deposit.
You will never be cool driving a Vauxhall.