Vehicle started making intermittent whining noise around 75,000 miles but Toyota service advisor at the time told me it was normal and since my transmission had been serviced on schedule, it was nothing to worry about. Around 135,000 miles the vehicle sometimes would operate completely normal, and at other times would suddenly seem to struggle to get up to speed especially on the highway somewhere between 20-60 mph. Also sometimes difficult to go at stoplights; but then would resume completely normal operation. The risk to us was we could have easily been hurt in an accident had the vehicle not been able to operate normally at normal speeds, leading to a collision. There were no warnings nor stored codes; the vehicle had received all routine maintenance on schedule including all major maintenance such as transmission services performed by a Toyota dealership. When taken in for this problem, they claimed that they were not able to replicate the jerky/intermittent issues during their test drive, but the whine was indicative of transmission failure and the transmission would need to be replaced. The remanufactured transmissions were on backorder with no ETA, which I was told could be 6-10 months of a wait due to a parts shortage. My service advisor recommended I trade in the vehicle instead because they could not guarantee the vehicle would be safe to drive and I could not continue to drive fearful of a wreck, so we had to do that, and the vehicle was traded in.