This interactive graph give a good indication of oil spec peformance compared. VW 507.00 looks pretty much the best overall.

sas-origin.onstreammedia.com/origin/lubrizol/EOACE...l

Edited by Hamsafar on 05/06/2013 at 16:33

API specs are so loose as to be completely inadequate for anything other than a Briggs and Stratton. None of the OEMs have much faith in API specs and most have developd their own specs.

Generally speaking, there's too much hand-wringing about viscosity (which is so temperature dependant) that a tight specofication is impossible. But the other aspects of oil composition are much more important.

Until recently I accepted the view that viscosity should be ambient temperature dependent - but I have seen a well-written article suggesting that since all ordinary road cars run at about 90 degrees C

Yes, oil coolers virtually nullify the effects of ambient temperature on operating conditions, but what are operating conditions? The big end bearings and cylinder bores won't be sitting at a nice steady 90C!

Then there's the issue of how you measure the viscosity. API quote a low shear test for viscosity, but most tribologists think that high shear viscosity is a much better indicator of oil performance on heavily loaded surfaces.

This matters because, unlike monograde oils, multigrades are non-newtonian and suffer shear thinning atr high shear rates.

Then there's the issue of ash content and EP additives. Heavily loaded cam lobes usually require some sort of EP additive-but too much of the wrong additive can really shorten the life of cartalytic convertors and DPFs.

Basically, OEMs know what their engines require. Why deviate withoiut good reason?

If I can turn the OP's question around a bit .............

In looking for some 507 spec for my VW Tiguan, I note that prices for supposedly compatable oil vary by a range of about 9 - 14 £/L.

Can I trust the less expensive stuff, or is it's compliance to the standard perhaps marginal. Maybe the expensive end eg. Castrol Edge, has things missing from lesser brands & is superior, or are we just buying a brand & getting ripped off ?

Situation not helped by the European "block exemption" law, such that a car manufacturer can't insist on their dealers using a particular oil for servicing - they can only list a set of specifications the oil must meet, together with a preferred oil

The extended oil drains of upto 2 years are interesting to say the least, As none of the filter manufacturers I've asked would recommend using a filter for more than 12 months. Alot of people have had filters break up and block oilways on vauxhalls with the cartride filters.

Vehicle manufacturers only give the minimum specification required and in the past it was based just on the API or ACEA ratings of the oil. API has been out of date for many years (even the Americans themselves will admit to that).

The Dexos2 spec is based mainly on the requirements of low SAPS for diesels with DPF's and GM are charging oil manufacturers a huge amount of money to be able to have their products licensed to use the Dexos 2 brand.

These days my main concern is that there are alot of fake oils out there and who knows what might be in that stuff?