 I've been having transmission issues since 12k miles and now I have just under 60k and now I have to replace the transmission. In the beginning, (around 12k miles) the transmission would SLIP, I guess that's the word I'd use to describe it. Anyway, I'd come to an intersection and when I went to press on the gas, the rpms would race as high as 4000 but the car wouldn't go no faster than 20 miles an hour. Twice I was almost in an accident because of this. I learned that I had to pull off to the side of the road, shut the car off and let it sit for a minute; I guess to reset the computer. I'd restart the car and it would be fine. This was an occurring matter, and I took it to the dealership and they couldn't figure out the problem. I had the transmission fluid service performed by nissan at just over 30k and the problem seemed to go away...for a while. At around 58 to 59k miles, I was hearing a whining noise coming from my car. I thought nothing of it really, just thought it was the air conditioner compressor making the noise. I scheduled an appointment to have it checked, and it turns out to be a bearing or some kind of belt in the transmission is going bad. I bought this car in Oct 2015 with 35 miles on the car so I'm the only owner, it's now July 2017 and I'm having the transmission replaced? Really? My advice to you is this, if you decide to buy a used 2015 Nissan sentra, be sure to get as much of the service info as possible on the car and if you're buying this car new, be sure to get the extended warrantee. You'll be glad you did.