Which oil spec?

[mattylondon]

Looking at the typical characteristic for viscosity (mm.sq/s) for each Castrol Edge oil weight, it is as so

Temp         5w30   5w40   5w50   10w60
 40C         66     75     109    163
100C         11     13     17     23

There are differences when the engine/oil is warm. I would still use VCDS and get two references for your current oil temp (I guess it's 5w30). Mrs Daisy v's Mr Marcin. Then we can see how hard your oil is working before making changes to oil weight.

[M-A8]

OK, I can see your point buddy
Is this is the data I can pull off the ECU now, or VCDS needs to be plugged in each time I go for the ride??

Slowly leaning more now towards 5w30

Thank you Matt, much appreciated

[mattylondon]

You'll have to log live data while driving mate.

[David's8]

Originally Posted by M-A8

I hear you guys, but I'm not convinced Castrol is putting same 5W30 oil everywhere just under different brand/name.
I just don't believe £2.80 per litre Quantum is identical to £10 per litre Castrol Edge.

Asda do some cracking deals on 5w30 VAG spec oil from time to time Marcin.....
Seriously though, (and I have posed this question elsewhere before) if it meets the spec then it meets the spec for normal driving. If you are, as Matty asks doing a lot of high revs stuff, the you should of course look for something that suits that. If it were the case that Company X (usually Brand name e.g. Castrol /BP ) produces a 5W30 that meets the spec but is adding some super-duper additive which achieves some fantastic bettering of engine life or whatever, then you bet they would shout very loud about it. But all they do is make some generic marketing statements dreamed up by cheap suited marketeers hoping you buy their product rather Company Y's as there is no real technical difference between them. In short - and I am happy to be corrected by anybody with sound technical information - IMHO the only real difference between, say Quantum and Castrol is the amount of marketing sh#te which Castrol has to pay for and recovers through higher prices. I stand to be corrected.

[Goran]

Marcin, if you really want to worry more about it, check out the High Temperature High Shear (HTHS) value for each oil. This value can give some insight about oils which are perhaps less protective as others.
Of course, annoyingly, some manufacturers don't quote their HTHS values. Some oils are on the 'edge' of the mentioned spec when it comes to HTHS

[Pug]

Perhaps unnesecary, but you could change the oil on a 6monthly basis? I don't have an '8', but I change my oil twice a year (about 5000miles) because I can.

I would not recommend any oil additives or chemical flushes. The safest method would be to change the oil twice, within a day of eachother. Alternatively look into a company called EDT. We used to have a machine at work.

It uses a very thin oil, heated to temperature, which is then flushed around the engine with a machine through a filter which catches debris. The machine also pumps the oil above the standard fill level of the engine, which captures more debris. I did it once on my ancient Fiesta, and the oil now stays clean between services. It's pretty much still golden coloured now. Obviously, we have never done an '8' so I can't vouch for its performance, however every car we did responded well to it.

Those additives strip critical components of the very thin coating of oil which is left behind by the oil. I've never come across a horror story, but reading hard enough into it, it doesn't sound wise.

And as for oil brand, Quantum is what we used at work, when we had a large VAG franchise earlier this year. Sadly the brand is no longer associated with our company. But the previous comment as for production for VW is correct.

Good Luck Marcin!

[MikkiJayne]

Originally Posted by David's8

IMHO the only real difference between, say Quantum and Castrol is the amount of marketing sh#te which Castrol has to pay for and recovers through higher prices.

Plus VAG UK are buying vast quantities of the stuff and we're buying LL3 at trade price. Look at the retail / ebay price of the two products and the difference is much smaller - Edge is £8/litre, LL3 is £5.60.

I do oil and filter at 5K on the S8 as well - my engine is brand new so its only on its second ever oil change

[Simonbartlett]

Quantum is what would be used at the factory or and vw or Audi dealer.

[briang9]

Not really sure why a debate is needed, Quantum is the brand produced by VW/Audi for their engines so meets the required spec (though as has been said it's probably rebranded Castrol or such like), and it's what Dealers and Audi Independant will use too...so sounds good enough to me..

[paulrstaylor]

Originally Posted by M-A8

1. Can of Wynns engine flush - 10min idle & 10min 2000rpm
2. Drain oil and fit cheap oil filter (if such a filter exists)
3. Pour approx. 10l of fresh Castrol oil
4. Can of Wynns engine flush - 10min idle & 10min 2000rpm
5. Drain oil, fit genuine oil filter and new sum plug with new washer
6. Pour approx. 10l of fresh Castrol oil.

Why not drive it for a week or two between steps 3 and 4?