Mobil 1 Tri-Synthetic 0w-40.
I use the Mobil 1 - Tri-Synthetic 0w-40 in both the engine and tranny. I've been using this since 10,000 Kms in the motor and the Tranny at 20,000. Never had a problem. I did over 260 Kms at the track last weekend, I kept checking the oil, but it didn't use ANY!!! The cars going in for it's 40,000 Kms service soon, it's done about 37,500 so far.
It's not easy to get a hold of this oil...... but it's great stuff. Abit expensive. As a test, Mobil got a M3 BMW put 1 million (miles?? KMS??) and pulled the motor apart, messured the parts, they were still within manufacturers Spec's. No wear, that'll do me.
Mobil agents selling this oil in nothing smaller than 20Litre drums.