On Alfa number 15
AO Platinum Member
Join Date: Dec 2005
Location: United Kingdom
Personally I cannot see the 5w-40 doing any harm..
It works fine in a TS and the TS is a very similar engine.
Plus I feel Alfa only specified the 10w-60 to help control oil consumption, and help prevent warranty claims on failed engines..
I can also see the arguement of following what the book says, but when did Alfa get everything right? Look at the original 72k cambelt interval as an example.