Subject: My experience using BG Syncro Shift II in a VW 012 longitudinal manual transmission (five speed) after 100K miles I realize that there has been some sporadic discussions in this great site regarding longitudinal transmissions and specifically the VW 012 transplanted in my FWD 2004 Passat TDI in 2013. The manufacturer specifies part number G-052-911-A2 which, based on my research, is most likely a re re-branded Fuchs Titan Sintofluid SAE 75W-80 (classified as GL-5 for some reason and sometimes I have seen the unofficial label of GL-4+). To be clear and upfront the VW 012 transmission in my Passat does not have "hypoid gear rear axles or limited slip". This is important because some transmission oils from Red Line and Ravenol warn not to be used in "hypoid gears" but you need to be careful to read the entire sentences as it contains words such as 'differentials' or 'rear'. So my personal conclusion is that these exclusions/warnings do not apply to my front wheel drive VW 012 longitudinal transmission. Back in 2013 I did some research and I concluded that a high quality full synthetic API GL-4 gear lubricant blended to SAE 75W-80 viscosity would be the right fluid for my VW 012 transmission. I originally had the Fuchs Titan Sintofluid SAE 75W-80 but I noticed that the cold shifting was not ideal so after some further research I chose the BG Syncro Shift II with a Viscosity, cSt @ 100Â°C (212Â°F) = 7.11. Now after nearly 100,000 miles with this manual transmission fluid I would say that has been successful for the most part. Of course there are always areas of improvements such as, at times, having difficulties to get into first gear and some notchiness going third to fourth. Again there was nothing major to make me change the BG Syncro Shift II earlier than 100K miles. So now I would like to look at my options to change the oil and of course I can stay with the BG Syncro Shift II which has become a little bit more difficult to source but I have not looked in detailed yet. So based on the above here are the options I am looking at in which I want to maximize the protection of my transmission with the best synthetics and AW/EP additives, for another 100,000 miles at least: 1) BG Syncro Shift II Viscosity, cSt @ 100Â°C (212Â°F) = 7.11 Pour point -43Â°C (-45Â°F) VI= 153 2) Mix 50/50 Redline Red Line MT-LV (Viscosity, cSt @ 100Â°C = 6.5; Pour point -76Â°F VI= 175) + Red Line Lightweight Shockproof (numerical specs unknown link). Note: yesterday I got a reply from Red Line via email recommending Red Line MT-90 (Viscosity, cSt @ 100Â°C = 15.5) for the VW 012 transmission. 3) Ravenol Transmission Fluid STF Synchromesh: Viscosity, cSt @ 100Â°C = 6.9 Pour point -60Â°F VI= 172 4) Pentosin MTF-2: Viscosity cSt @ 100Â°C = 7.7 Pour point <-76Â°F VI= 177 5) Pennzoil Synchromesh Fluid: Viscosity cSt @ 100Â°C = 9.08 Pour point -50Â°F VI= 208 (this information is from a PDF file that I have saved sometime ago dated March, 2000) Right now I am discarding the MT-90 recommendation as too thick for colder temperatures. The VI for the Pennzoil one needs to be re-verfied but I do not have more up to date information (anyone?). For the time being I am inclining to either options 2, 3 or 4 in this order. Cost is similar and not an issue here for obvious reasons. Your thoughts?