I just started using Motul 8100 E-tech 0W-40 in my 2002 VW W8 Passat (8 cylinders) and toying with the idea of 10k mile OCI. The VW manual says 10k mile OCIs, but prior to the Motul I've always done them at 5k since the dealer used castrol syntec 5W-40. But now that I'm using a true synthetic (grp V), thinking of going to the 10k mile OCI. I'm still in warranty, so 10k OCIs would be my limit. Just don't know if I'd be creating problems. I had one service tech tell me I risk sludging with the 10k mile OCI. What's the consensus?