Transmission Slip

[mrossirr]

99 Sport with 51,000 mi.
Slips about 40 to 50 percnt of the time 2nd and 3rd gear.Took it to my dealer which I have used before with no problems. They replaced the seperator plate,valve body gaskets and filter. Picked it up Friday and it still slips. Taking it back Tuesday. What should the next step be to repair this transmission - rebuild ? Should I take it to a tranny shop like Cottman or Amoco ?
Thanks in advance

 

[Robert]

Pretty low miles for needing a transmission already although it is exibiting one of the signs that mine did before it needed rebuilt. Last summer, when accelerating lightly, I could hear the RPMs rev up just a bit before upshifting. Mine also had a harsh clunk when slowing down to a stop and a bad clank when going from R to D or vice versa. I first tried the updated seperator plate, gasket and switching to Amsoil ATF but it didn't help a bit. End result was that I needed my transmission rebuilt, but I had 95K on it at the time.