'01 Jetta VR6, warranty is over. Unfortunately the thing doesn’t have a dipstick on the tranny. I found directions online for changing the fluid, including how to check the level. It isn’t easy and requires diagnositc software to check the fluid temp. Supposedly a valve won’t open until it hits a certain temp, if the valve is closed you won’t get an accurate reading.
Sometimes there would be a harder than normal shift from 2nd to 3rd after driving on the highway for a few miles.