Engine oil Castrol or Shell

I would drain that oil with the Marvel in it and use use 0w-40 Castrol Full Synthetic (Made in Germany/Belgium). You can get a 5 quart jug at Wal-Mart for less than $25 usually. It's probably the best "over the counter" oil you can use in a VR6. Widely used and highly recommended.

These days I do use T6 because I know the winters in south Texas aren't cold enough to worry about running anything lighter.

People like rotella because it’s a high zinc oil and subarus just like high zinc.

I run the Rottela 15w40 in my stock 05 Subaru Legacy GT (EJ255) and my mk4 supra turbo. Haven't had issues with the cats on the Subie, I do plan to remove them tho

Rotella 15W-40. I put that shit in everything. My Yukon, my Fit, and all 3 motorcycles. It’s legit.

We used to commonly use Rotella in our heavily modified Mazdaspeed 3/6's to combat the same issue. It worked great and the only problem we ever had was with what we called the "black death".

I went with the Castrol Edge 0w-40 because it's a great oil with a good PAO content. It's also fairly inexpensive. I'll sacrifice the rebate on Mobil 1 as this oil seems to hold up better for my driving style over 10k miles.

I typically use Castrol Edge 0W-40 at 5000 mile change intervals unless my annual service interval comes up at the dealership.

I personally use the Castrol 0W-40 that meets the VW 502 spec. Per the Bob is the Oil Guy forums, it’s one of the best oils out there and is available at a great price from Wal-Mart, at ~$25 per 5qt jug. I’d use this oil in any VW and not think twice.

I run German (Belgian) Castrol, which comes in a 0w-40 or 0w-30 weight. In general, it's better than the US spec stuff that sage149 posted because Europe has stricter oil standards than the US and it holds better certifications like MB229.5. I mainly run the 0w-40, and while I only have 13k miles, it does include 4 track days and the oil level doesn't change in between oil changes.