Original owner car, as close to bone stock as I can keep it. The transmission was never out until a year ago when I had it rebuilt by a local shop of good repute. After a year it developed the following problems: -- Up-shifts into overdrive at about 15 mph. -- Down shifts out of overdrive at about the same speed, maybe lower. So it is fine on the highway, but completely undrivable around town. It is the correct original numbers-matching transmission. Dropped the pan and verified that it has the original GN valve body. Did not check the governor yet but doubt it got swapped -- tranny shop said the original valve body and governor were retained. Tranny shop had no ideas, plus out of warranty. They finally gave up. Another tranny shop messed with it. My mechanic paid them, but they could never solve it either and finally gave him his money back and told him to never come back. At least not with my car. The speedo reads low; guy at a speedo shop says it is just fine. Ideas?