Transmission Failure problems of the 2006 Toyota Sienna

Transmission failed at speed on I-95. With van, cargo and 5 occupants at traffic speed in the right lane, the engine raced, the van dropped out of cruise control, and we drifted to a halt on the side of the road. While moving, I shifted to "4" and "3" then back to "d" with no acceleration. Had we been in any other lane, the transition would have been harder and more dangerous than it was. The engine and other van systems continued to operate normally. When we were stopped, no forward gear produced movement, though reverse worked. A check showed the transmission fluid at normal hot level, though it was darker than normal. It took an hour on the side of the road, traffic passing alongside the van very close and very fast, before a aaa tow truck got to us. After a tow to a Toyota dealership, the transmission was replaced under the powertrain warranty due to a reported failure of the forward sprag. The failed transmission was retained by the dealer.

I bought a new 2006 Toyota Sienna van. From the beginning, the transmission drops into neutral as the vehicle slows for stops. Upon acceleration to move through a stop sign or light, the transmission hesitates in neutral, leaving those following about to rear end the vehicle. Or, if you accelerate, the vehicle lurches into gear throwing passengers forward. I have mentioned this problem every time I have had the vehicle serviced. The serviceman acknowledges the problem, and states that Toyota claims it is a means to save the transmission. The jerking on the transmission as the vehicle goes into gear after a stop cannot be good for the vehicle. The serviceman further stated that other car models made by Toyota had experienced the same problem, but that a "computer patch" had been made available that solved the problem. He said that no such patch has been made available for the Sienna vans. My concern is that I will end up rear-ended because of the hesitation or that the transmission will fail.