Hello. My names Mark. I have been lurking for a few weeks but thought I'd finally say Hello.
We have been running bio @ 100% for nearly 2 years. We change our oil every 3000 and have had no issues. Running it in several 300tdi's and 1 2.8tgv. Changed fuel filters at 100 miles, 500 miles , 1000 miles and then with the oil changes. Over a few vehicles we have done close to 100,000miles with no issues. Just about to start running in a TD5 but probbaly at 50% bio to mineral instead. Bio diesel is far more enviromentally friendly as long as it uses waste oil in the process as it is a waste product rather than an orginal one. Using Bio does also lower your emmsions by up to 80% (I have my MOT emmsions statement to prove it). There is a huge difference in quality of bio depending on the base oil, which is why some of you are getting poorer BHP and MPG. Stick with it and either make it yourself or find a good supplier you trust. A good sign is when they use it in there own trucks. (Quite alot of them don't!) As for rubber seals. Anything post 1992 should be OK. If you have a LUCAS fuel pump then they don';t like it but BOSCH is absolutley fine. Hope this helps.