Do diesels require a differant oil to a petrol engine?

VAG do have a certain VAG code for oil thats certified for use in PD diesels...
 
Actually yes, slightly different detergent properties with diesels, base oil is probably the same with similar shear forces, but as petrol is alot more aromatic it's very different to deal with, on cold start particularly.
 
Mmmmm - what happened to the rest of my first reply /ubbthreads/images/graemlins/confused.gif

No, it isn't just a marketing gimmick though it depends on the engine: pre-TDI, TDI or PD - you haven't said which but from your profile it's a TDI (non-PD) and you need VW505.00 or equivalent.

My Golf GTD ran for years on the same oil as my 16V GTI. My TDI runs on any 10W/40 VW 505.00 equivalent,currently it's Morris's Multivis and my PD runs on VW 505.01 or an equivalent but (I've just checked) my top-up bottle is Castrol 0W/30 SLX Longlife.....

Now that's got me thinking, it says it "...meets the stringent requirements of the Audi AG Longlife service concept..." and is "recommended and approved in accordance with VW503.00 and 506.00 (05/99).

Looking at the service schedule, a 4-cylinder TDI with unit injector system (which I take to be a PD) requires an inspection service - not Longlife servicing - and should definitely use VW505.01 so someone has put the top-up bottle in the car....

I hope all that hasn't confused anyone except me.
/ubbthreads/images/graemlins/noidea.gif
 
Newer diesel engines are alot closer than their older counterparts to lubricate to petrol engines due to tighter tolerances etc