[Diesel_Dave]

I saw that headline in Diesel Power as well. I'll have to go back and look at it again.

Before I started I was expecting an increase of ~3-5% in mpg, based on results I'd seen. It's hard to get a firm number, but so far I'd estimate I'm getting better than that, maybe in the ~5-10% range.

Last night I broke my evening commute record with a 45.0 mpg run. My previous best was 43.5 mpg. This morning I set another morning commute record with an astounding 49.1 mpg run. Recall that with the 15W-40 conventional oil, my previous record was 45.5 mpg. So in less than a week, my morning record has increased by 3.4% and the evening record by 7.9%.

Unfortunately, it's darn near impossible to do A-B-A teting with oil in the real world.