Recently, I purchased a Corolla 2007 model automatic transmission car. On the same day, I changed the transmission oil (ACDelco ATF Type-III (H) fluid). Whenever, I slow down (10-20 KM/H) the car due to round abouts or speed breakers and again push the accelerator, I feel a transmission slip - the engine rpm increases but without speed. At that time I put the gear in "L" then I move and thereafter I bring it in "D" mode. On high speed there is no problem or jerk. When I inquired from my previous owner he accepted the fact that he was also feeling this slip. Can anyone please help me - this is due to oil that I am using or due to any other problem. Should I try with Toyota ATF T-IV oil?