u/Gindizzel

Hello folks! I’m suffering from limp mode in my car and just replaced the turbo so o scanned with OBD11 and saw that I have some transmission codes and unfortunately realized the hard way that transmission fluid needs to be done every 40k miles. I have about 190k on the car and can’t fully guarantee if the service has ever been done on this car but I took over ownership at ~45k miles. Anyway, I’m trying to save a buck and have seen that it’s “as simple as doing an oil change” which I do often myself on this vehicle and saw some DIY YouTube videos on how simple it seems to do a transmission service on this model car. I called a local mechanic and he suggested to not even do a full drain and refill because it can kill the transmission fully by doing so since the car is so acclimated to the OG fluid that’s in there now. He did recommend that if I were to try and do this service still, to mix some new fluid in with the old fluid and not do the full flush. He did not specify how much to mix in or how long to wait to add more and drain more but essentially doing this until all fluid is mixed to where it needs to be done at whatever point that is. Long story short, I need some recommendations on how to do this myself. I feel confident on the process, I just am unsure how many qts or how much to mix in and how long to wait to add more/drain more later on. Any suggestions would be great!!! This is an automatic 2017 Volkswagen Golf Alltrack SE with about 190k miles on it.