Engine oil Castrol or VALVOLINE

All oil changes on this car have been done with Castrol Syntec 10W30 Full Synthetic and an OEM Mazda Filter.

From what I can find, Castrol makes a 0W30 longlife oil which can be used in VW engines which have sensors which support the longlife service regime. According to this regime, oil change intervals can range from 9,000 miles or 12 months to as long as 30,000 miles or 24 months - IF the sensors will allow such an extended interval.

In the early years only VW dealers carry Castrol Syntec 5w-40 oil which is where I am always getting from.

Valvoline Synpower 5W-40 also meets Volkswagen specifications.

I had to top off once and used Castrol Syntec, which is about $3.50 where I live.

I had to top off once and used Castrol Syntec, which is about $3.50 where I live.

My favorite is simply Castrol drive hard. I run it in all my engines except the VR.

i use valvoline 5w 30 and it hasent done me wrong...yet

I also have a 2.0 and run the valvoline synthetic. I started after 2500m and am currently at 29k. No scientific results here other than keeping track of mileage in a little notebook and looking back at the first month compared to the most recent - I'm averaging about 7mpg more.

All these problems are not present in the Valvoline SuperSynth 5W-40 sample. Furthermore, the results from this Valvoline are well below the Universal averages for this engine. This suggests that I should be able to run this oil for at least another 1000-2000 miles and still get an excellent report out of it! With it, my engine runs bit smoother and quieter especially at idle. At high engine speeds the engine feels more responsive and more lively. Another difference is that with Valvoline, I am observing improved efficiency. My 2.0 broke its own record of fuel efficiency: 34.3 miles to the gallon on high way. The improvement is 3.3-3.9 miles per gallon compared to Mobil1.