Why I sometimes get a small jerk during automatic change of gears

harshaqdc , Transmission may require servicing/fluid/filter change if it has not been done in quite a while. If you are new to the vehicle this may be normal operation. If you have owned the vehicle for some time and the car has just started doing this check the transmission fluid level and top up to recommended level and look for any signs of leaks and have repaired. If fluid level OK, have checked for trouble codes to help diagnose the issue. Could be a sensor/shift solenoid/ torque converter lock up/computer,etc. issue. Some of the auto parts suppliers offer free code reading like Pepboys, Nappa, Advanced auto parts,etc and some of the guys are very knowledgeable and may have seen the issue often and put you on the right track.

If no luck there have checked by a good local transmission shop and estimate for repair. Good luck. I hope this helped you out, if so let me know by pressing the helpful button.