Oil change time castrol edge

[awolfinsheepsclothes]

Oil change time castrol edge 5w30 and 5w40 are both on special offer at tesco
For £25 any thoughts anybody? Should I go for the better 5w40?
Does it meet Audi specs for a AQH?
Please don't insult me by saying look in the useless owner manual or type in my reg and model number into a oil supplier web site as they all give different grades. Cheers Dave

[HPsauce]

Originally Posted by awolfinsheepsclothes

Should I go for the better 5w40?

How is it better? Surely lower viscosity is better, for both engine wear and friction/power loss.

[Dezzy]

Just use water

[awolfinsheepsclothes]

5w is the cold start the second number is weight when hot.
Drezzy stop mucking around this is a serious subject! Still? Sparkling? Distilled? Tap? Rain? Flavoured? Soft? or Hard? You can't just say water this is a technical forum!

[The_Laird]

Originally Posted by Dezzy

Just use water

"in what shall I fetch it, dear Liza, dear Liza?"

All together now......

[ainarssems]

They are probably both OK but only way to say for sure is to check for specifications on the can to see if and which VW specifications it meets. I think AQH engine need 501 01, 502 00 spec oil .At £25 why not go for Quantum oil which is the official VW oil:
http://www.ebay.co.uk/itm/GENUINE-VW...AAAOSw5VFWFlGu
or
http://www.ebay.co.uk/itm/Quantum-Lo...0AAOSwJkJWl8iL

As for 5W30 or 5W40 are only a numbers for representative oil viscosity and does not necessarily say which is better oil. For one thing I would say that bigger difference between 2 numbers is better for example 5W40 is better then 20W30. There has been a push for thinner oils like 5w30 or 0w30 as they being thinner mean lower fuel oil consumption and less CO2 that manufactures can put on spec sheet but often at cost of other properties.


There is a nice comparison tool here where you can compare different specification oils and their different properties: https://online.lubrizol.com/relperftool/pc.html

[Goran]

There is also some factor called High Temperature High Sheer (HTHS) measured at 150C
If I understand it correctly this is the measurement that can protect rollers/bearings better.
Although our engines are not turbo so shouldn't get up to really high temps.
I switched to a 5w40 oil one of the reasons was that it had a higher value for this HTHS factor. On the downside some 5w40 oils have higher viscosity when cold which could be a bit worse for the engine?

https://www.waermeaustria.com/upload...e-5w-30-pi.pdf
Edge 5W30 HTHS = 3.5
Cant find a HTHS for Quantum Platinum 5W40.
Fuchs Race Pro S 5W40 HTHS = 4.07
Mobil 1 0W40 HTHS = 3.8
Shell Helix Ultra 5w40 HTHS = 3.68

I can't remember where I found it before so take this with a pinch of salt, those Audi specs for our engines call for a minimum HTHS=3.5 so Edge is ok, just.


Oh yes just remembered, perhaps its worth considering viscosity at 100C? Higher is more protective I guess (up to a point)?

Edge 5w30 @ 100C = 12
Quantum Plat 5w40 @100C = 13
Fuchs Race Pro S 5W40 @100C = 14.89
Mobil 1 0W40 @ 100C = 13.5
Shell Hexix Ultra 5w40 @100C = 13.1

- here I found this for two Audi specs. 3.5 HTHS is minimum.

[Goran]

On the other hand, please ignore me
I'm sure all the oils that meet the Audi/VW spec. are fine.

http://www.ft86club.com/forums/showp...2&postcount=19

[Dezzy]

Originally Posted by awolfinsheepsclothes

5w is the cold start the second number is weight when hot.
Drezzy stop mucking around this is a serious subject! Still? Sparkling? Distilled? Tap? Rain? Flavoured? Soft? or Hard? You can't just say water this is a technical forum!

Salt

We use water lubricated bearings a lot on ships as for some reason they always seem to be very close to a huge supply of it.


I personally always use Quantum oil.

[Pug]

Audi use 0-30. Look for specs 502.00 and 507.00 as they superceed the old specs for Longlife and protection etc. Quantum is cheap on eBay at the moment for 5w30. 5L for £20.