Last summer, noticed uncommanded downshifting when driving at 40 mph. Brought vehicle to dealer for reflashing of memory, recommended fix. Some $287.00 later, vehicle still downshifted, although at different speeds.

Today, while on the interstate, odometer stopped working and speedometer read zero, while tach indicated 2600 rpm, rolling at about 65 mph. On arriving home, vehicle would not climb driveway, even at 4000 rpm.

Dealer says spline may have separated. Even at 1500 rpm, vehicle will not move. Shifting to reverse is accompanied by a loud "thunk." A remanufactured transmission is available at $5000.00 plus installation, a lot of money for a five year old car. Still, it has been a warhorse, other than this transmission problem. So far, the major design issue I have is that the washer system for the windshield freezes up at below 30 degrees, not an issue unless you are driving in a blizzard in Michigan.

Has anyone else had this problem? How did you resolve it? Would like to solve it for less than nearly $6K if we possibly can.

Update from Feb 23, 2013: Here's the sequel. Next day the service manager, who had diagnosed the problem initially, called to say his "top expert" had determined it was not the transmission at fault, but rather, two turbine speed sensors, sensors that tell the transmission what to do, had shorted out, and had to be replaced. The parts cost about $180.00 but the labor added $680.00, so with taxes, the bill was $917.00, still a lot less than replacing the entire transmission. Car now drives normally. Still has some uncommanded shifts at about 43 mph but that is the software, not the transmission.

Were it not for an honest guy, I could have been looking at a major expense. As it is, the car is good for another stint, hauling grandchildren to the park.