It depends on if it is a manual or automatic transmission. For the manual transmission, there is a 17mm Allen plug in the side of it. Crawl under car and take the plug out. You can buy a fluid pump for about $20 at an autoparts store and the 17mm Allen wrench is about $10 at sears. It is pretty easy on the manual transmission, hardest part for me was finding the 17mm Allen wrench.
Automatic transmission?? you cannot put the transmission fluid in by yourself you have to take it either to a V.W. dealer or someone who services these types of transmissions the fluid has to be pumped inif you notice there is no dipstick to check the fluid level that's because they use this probe the stick into your transmission to see how much fluid you have the probe costs about $1500 dollars expensiove yes keep in mind it will cost about $20 a quart the reason why I know this is because I am having problems with my transmission in my 2001 jetta if you have any more questions let me know. firstname.lastname@example.org
I know for all the cars we have had ,that if it is an automatic transmission you have to pour the transmission fluid down the Transmission dipstick (where you check the fluid at), But if your car is a 5 speed manual you have to check the fluid under the car and pour it in there. The system is a closed system, its meant to last the life of the transmission. This being said there is no dipstick at all on an automatic jetta I'm not sure of the years but the 97's don't have one. There is an area where a dipstick can be added in the front of the transmission near the radiator you will have to look for it and you can buy the $19.00 mod piece on eBay or elsewhere.
I have a 1996 VW dl jetta and to add the transmission fluid is on the right front side of the car underneath by the tire. My husband had to put it in that way. But he said he will never go through that again. To add tranny fluid you have to go to the garage. Because they have to pump the fluid in the tranny. There is no place to check the tranny fluid like a reg. car? Crazy but true.