I have a 2013 Outlander Sport with 55,000 miles. Around 35,000 I notice a lag in the cvt transmission. Best description is like driving a standard transmission, slowing down, then accelerating without changing gears. Also when coming to a stop, sometimes the transmission feels like it's downshifting and about to push you into the back of the car in front. I had it checked twice by the dealership who said "there's no error code" "we drove it and it seems fine". It's not fine. It's not smooth. Fortunately I have an extended warranty for when it completely fails. Any ideas?

Thanks in advance.