Having intermittent problems with the overdrive. Usually, it works fine. Every once in a while, the overdrive will simply not work. It may be working fine, then you park, and when you start again, the overdrive won't work. Other times, you can be on the freeway, with overdrive working, and with heavy traffic you have to slow way down, and then when you speed back up, it wont shift into overdrive. It will start working again, after stopping and shifting it into park and back into drive (but not always).
It seems like it most likely and electrical issue, as the trans shifts fine.
Any thoughts?