With modern low sulphur and 5% bio diesel it would appear that the lubricating properties of the fuel are decreasing. I stumbled across this on my transit forum and have since been adding 2 stroke to the van. So far i have noticed it running slightly smoother, a 10% increase in economy, less squeaking of the EGR and can hear the turbo spinning up more freely. (i think)
Now so far i havent found too much info on adding it to cars with a DPF even though id love an increase in fuel economy but it might be something the E53'ers want to discuss (try at your own risk


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