97 Pathfinder 4WD goes in & out of overdrive

[petnieto]

My 97 Pathfinder goes in and out of overdrive. It doesn't seem to make any difference whether I'm going 55 mph or 70 mph. The overdrive on/off button does not seem to have an effect either. It doesn't do it constantly(hunting) and I can't tie it's occurence to any particular driving situation or condition. The dealer says it's likely(best guess) the tcm that's at fault but they could not guarantee their prognosis because it doesn't throw any fault codes that is after leaving it with them for 3 days. I have already replaced the tcm once but with the same results. I'm inclined to believe that suspect is mechanical like a stuck valve but short of replacing the transmission there's really no way to check. Just hoping somebody else may have a similar experience that they can share with me or maybe some of our bright minded techs out there can shed some light into this mystery. Any ideas will be greatly appreciated.
Modified by petnieto at 11:53 PM 6/2/2005

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