Higher lubrication then standard diesel. I’ve been reading of high pressure fuel pump failures on the TDI’s and it’s a $10,000 service job! The HPFP uses the fuel as lubrication and bio has more lubricity. B2 means that it’s 2% bio (soy usually) and 98% normal diesel giving it just a bit more lubrication. Granted I wouldn’t have to pay for this job given the warranty, but I also would prefer this not happen.