Odd 2D Torque behavior

In 4.4 when I used 'rigidbody2D.AddTorque' to roll a ball left and right, immediately after i released the button that was applying the torque, the ball would lose all the force that being applied. For example, if it was rolling up an incline, it would quickly slow down, lose its momentum and roll back down.

Since 4.5, using the same method results in ball keeping its spin for a very long time. For example, if I am going up a steep incline, and I release the button applying the torque, the ball will continue to roll uphill as for a very long time at a low speed, its not its momentum carrying it up the hill, but its as if the torque is still being applied, but gradually gets lower. Eventually the ball does stop rolling.

I have tried fiddling with everything available to me, such as angular drag, but the results often end up poor, or effect other physics of the ball.