Anyone suggest a decent oil to help improve mpg / reduce wear

[ItsJAYKAY]

My previous car was a the TDI 130 - with this i used Millers xfs pd oil - it improved mpg performance greatly.

Has anyone any suggestions to whether or not there is an oil out there which will do similar for the 2.0 FSI?

[wantmygti]

No idea but it has to meet VW standard 504 and most people seem to stick with Castrol Edge I think.

[ItsJAYKAY]

Is the 504 a new standard? I can only find specs for the petrol cars such as 502, 503, and 503.01.

I have gone for the 502 as I dont really need the benefit of the longlife requirement of the oil.

[wantmygti]

I believe 504 oil does not break down under the exdtreme temperatures of the turbo. Check the manual, for the other standards allowed but i thought 504 was the one for the long life intervals and as such is the best oil to use even if not on the longlife regime.

[Hully]

I use 503 spec as it says either is suitable in the manual. Anyone know the difference between VW spec 504 and 503? 

[wantmygti]

isn't 503 T+D oil and 504 longlife oil?

I'm sure TT (has he left these ranks??) always swears that you should use 504?

[Rhyso]

isn't 503 T+D oil and 504 longlife oil?

I'm sure TT (has he left these ranks??) always swears that you should use 504?

sounds right to me.

TT has suggested many times that the longlife oil should be used even if you are on T&D servicing as it provides better protection to the internal parts which is esstential if you drive your car particularly hard on a regular basis. 

So for those who have had your car remapped switching to longlife oil will provide better protection against the additional stress the engine is now under 

[Hully]

isn't 503 T+D oil and 504 longlife oil?

I'm sure TT (has he left these ranks??) always swears that you should use 504?

sounds right to me.

TT has suggested many times that the longlife oil should be used even if you are on T&D servicing as it provides better protection to the internal parts which is esstential if you drive your car particularly hard on a regular basis. 

So for those who have had your car remapped switching to longlife oil will provide better protection against the additional stress the engine is now under 

The manual states that 503 is long life too. Futhermore, the oil itself states that its long life. The only thing I could think of was that one was 0w-30 and the other is 5w-30. Any ideas? 

[wantmygti]

Not really. I can only guess that the higher number 504 is a higher quality standard than 503 but I'm only guessing.

Come back TT, all is forgiven...

[Hully]

After a bit of research from various sites including the Castrol site, I think I've worked it out.  VW spec 503 is 0w-30 grade, known as Longlife II. It now seems that this has recently been replaced by VW spec 504, or 5w-30 viscosity. Both oils are suitable for Long Life on the GTI. I would imagine that VW 503 will become harder to find as time goes by due to it being replaced by 504. 

The only difference between 0w and 5w is the thickness (viscosity) of the oil and its ability to handle the cold weather. 0w performing slightly better in the colder temps than 5w. However, I doubt that you or I would be able to tell a difference unless we drove our cars north of the Arctic Circle.