[Art Sale]

Ford recommends use of 5W20 Oil for the 2001 Vulcan SE(and perhaps other current engines). Does anyone know the advatage of this grade over others available at a lower price -say 5W30 or 10W30. I would guess that fuel mileage might be improved, but by how much?
5W20 is priced about $1.50/liter higher in my area, and you have to look around to find it. Is it worth it?
Art Sale

 

[jason8225]

I've been using Valvoline full synthetic 5w30 for at least the last 3 oil changes (more than that i think) and I get 30+ MPG on the highway (with K & N filter, air silencer removed and Flowmaster muffler).

 

[-qaz-]

5w-20 gave me about 2mpg more with my 94 vulcan then 5w30/10w30.

 

[kms250]

The 5W-20 oil would flow better through an engine compared to a 10W-whatever. The first number is the base weight and the second number is the polymer added to enable the oil to act like the higher number as well. So in a nutshell, the first number is the base weight, lower=more oil output from the oil pump, however this is required to keep the temperatures lower, higher=less oil output from the oil pump but not as much oil output from the oil pump is required to keep the temperatures lower.

I guess it's a matter that the engineers at Ford decided a higher amount of oil pumped out of the oil pump with better flowing is better than a lower amount of oil pumped out of the oil pump with less flowing.