Engine oil MOTUL or OEM Audi

It might be due to a difference in oil viscosity. With usage the Motul oil has sheared down to 30 weight which makes the engine run more freely and cooler as compared to fresh Castrol which has not accumulated enough hours to lose viscosity. It's been well documented that a viscosity decrease lowers oil temperature.

The 8100 X-Cess. It has actually improved my fuel economy!

Well the oil change itself is unbelievably easy and clean. The Motul oil works well for me.

I run Motul in the Subaru with a bunch of track days and it has had no oil related problems and does not burn excessive amounts of oil with almost 75,000 miles.

Have you given the Motul Specific 502.00/505.00/505.01 a try? I switched to it years ago on my mk5 rabbit (140k miles or so over the past 5.5 years across 3 cars) with excellent results. It is a mid SAPS oil like the x-clean as well.

Cost me 62 dollars using motul xcess 8100 5w40 and took 15 minutes start to finish.

much to my surprise, the motor has not burned a drop of oil in the first 50,000 miles (I change the oil every 5000 miles).

I've used Motul in my Golfs for years, good stuff.

Sounds like you already have your answer, but yes, the Motul 8100 X-Cess is a good oil, probably better than their VW specific oil.

Been using Motul on my 3.2 for the past two oil changes. Haven't had any issues.