Question Dumb Question? 506.01 for 2 liter GLS? I note that the 505.00 that I have started buying also are VWAG approved for 502.00. So I am using it on the 2000 GLS. However, after this cycle, I am actively considering changing to 506.01 for 50 Km OCI for my 2003 TDI. I have done a search and read 10 threads on 506.00 and 506.01. I have not found an answer for this admittedly non-TDI Question: Question: 1. Is 506.01 VWAG approved to replace 502.00? can someone point me to the URL or string? 2. If there is no explicit VWAG approval, what is the informed consensus by the oil geeks? cheers!