What is the correct oil for the 2000 Audi A6 2.7T Allroad?

Shell Helix Ultra was recommended, but I like the Castrol Edge Sport. It is designed for older high performance cars.What is the correct oil for the 2000 Audi A6 2.7T Allroad?If the have the same ratings use the Castrol if you preferr. e.g Shell 0W-40W/ Castrol Edge Sport 0W-40W means same properties just different brandsWhat is the correct oil for the 2000 Audi A6 2.7T Allroad?Use what you like as long as viscosity is rightWhat is the correct oil for the 2000 Audi A6 2.7T Allroad?Go w/ what you know