Galant A/T late-shifting

[peterm_1004]

Hi Gents,

This is my first post here and am hoping someone out there can help.
I have a 2000 Mitsubishi Galant V6 Sport with Auto box (triptronic).
It has been a great car up until last week when I noticed the MPG falling through the floor. On investigation it turns out the Auto box isn't shifting up until much higher speeds i.e. at 30 MPH it will hang in 3rd gear and not shift up to 4th until about 37 - 38MPH.

Anybody any clues....I have tried leaving the battery off overnight hoping this would reset the ecu but no luck.

[peterm_1004]

Bump!!! are these normal speeds for shifting on a 4 speed auto box?

[jamest001]

Take it to an AutoZone or Advance Auto if you have any in your area. They will hook up a code reader for you free. We had trasmission problems on our 1999 Galant and it turned out to be (1) a bad transmission module (can't remember the code), and (2) low backflow pressure in a transmission line. A flush & fill cleared the line and returned the pressure to the right level.