It has antidepressant actions like its cousin venlafaxine. That drug has a reputation for being difficult to quit, so you may experience atypical symptoms different from the expected opioid withdrawal. Then again, you might not notice them if you're going through opioid withdrawal.
Because of all this, it's probably better to taper off tramadol when you can.
EDIT: Thread re-opened. Sorry OP, I thought your question was answered.
Please feel free to ask away, we have answers.