Shuddering problem in Hyundai i20 Elite
 

I own a brand new Hyundai i20 Elite since Dec'2015. I have driven around 8000 KM. Until recently, my car has been occasionally shuddering when I try to accelerate.My drive is limited to my to & fro journey from home to office (7-8 Km on one side) and the occasional shudder occurs at different area of my journey (not usually the same area or point).

Just for an example, I was driving uphill on a bridge at 2nd gear with RPM at around 2000-2500 and when upshifting to 3rd gear, after complete clutch release and passage of 5 seconds, i feel this shuddering 2 or 3 times. I am unable to understand what is causing this problem. This shuddering do also happen while I am driving on plain road also

During the 3rd week of the April'17, I took my car for checking this problem to Hyundai Service Centre and they were unable to detect anything. But I cannot figure out why this shuddering is happening every day twice or thrice in my journey which does not seems to be coincidence.

Further, I would like to add that this shuddering problem has started occurring after I was driving with 7 of my family member (6 of them adult and 1 child member). During my return journey, I felt this shudder continuously during my return journey. In case, I was driving in higher gear, the noise of the vehicle would have been different which was not the case in all these events.