From Faq sheets in members area
Synthetic and semi-synthetic oils
Synthetic and Semi-synthetic oils are fine if your engine has done less than
25,000 miles and you can afford the extra outlay (which is significant). They are
not a cure-all, they will not stop your engine burning oil and they will not replace
worn metal surfaces. If you chose to use these oils after the wear has taken
place, you may or may not slow down the continuing rate of wear. In my opinion
they are a waste of money in engines having covered over 25,000 miles
From here:-
http://www.igmaynard.co.uk/bongo/member ... icants.pdf
I have semi but it was cheap on e-bay 10Lts Comma 10W 40 at £20 inc p&p
Sparky
The Bongo has gone. Long live The Bongo
Hymer Camp Swing 544/Fiat Ducato 2.3jtd