So before buying this 2015 Jetta TDI i read a lot on this forum and saw lots of people were getting beyond the advertised 46 mpg even after the phase 1 fix. I bought my Jetta with 10K on the clock and a 6 speed manual which i had to fly to a dealership and drive it 7 hours home after buying. Im on my 3rd tank as my daily commute is at 100 miles round trip. Im pulling 40-41 mpg on all three tanks, with the first one being all highway. No way this is normal. Optilube XPD gives me a gain in my super duty truck but had no effect on the TDI. I have verified trie pressure at 38psi. I have to admit this car will coast long distances with significantly less resistance and more rolling than my old civic. Im just disappointed by this mileage and seeing other people on the fourms doing 20% + better performance.