Volkswagen Repair: Transmission Problems, internal leaks, speed overdrive

Question
Hello, My question is 2-part:

Question 1: On a 98 Jetta 2.0 automatic, the transmission is having trouble shifting when accelerating (winds high before shifting to next higher gear) Any ideas on a sensor or anyway I could fix this?

Question 2: What transmission fluid should I use when replacing fluid, and where how do I go about replacing the fluid (no dipstick)

Thanks for yor time answering these questions!

Answer
Hi Chris;
Volkswagen automatic transmissions are not user freindly!  There is a special tool that is necessary to fill the transmission, and you have to know what the temperaure of the fluid inside the transmission is while you are adding the fluid.  Shifting problems with Volkswagen transmissions...especially 4 speed overdrive transmissions...which yours is...are almost always internal leaks.  That means that the fluid is "crossleaking" and trying to make (for example) second gear, and third gear shift at the same time...which can't happen, so the transmission starts to ask questions of everything else on the car, and finally figures out "Oh, it's second, and not third."  And then the shift finally happens.
There is no easy repair.  The transmission either needs to be rebuilt...not my first choice...or replaced with an equivalent transmission.  I wish I could tell you that you have a couple of easy decisions to make, but I can't.  You will have to decide if you want to spend $2500.00, to $3000.00 to replace your transmission, or not.  That's pretty much it.  Good luck.