Has the check engine light come on? Have you checked to see if there are any trouble codes stored in the computer?
Keep in mind, I assume you checked the transmission fluid and it is clean and full. A few things can cause what you described. An engine misfire, slipping clutch pack, bad torque converter, bad torque converter clutch.
Let me know.
Thursday, December 7th, 2017 AT 6:59 PM