Now this is one question that has no clear answer. It is not like all automobile engineers get the same package and same with IT professionals too. Each student gets the package based on the placement, company, job profile etc, his/her CGPA, performance in the interview. Yes, IT sector is known to pay well but there are companies which pay less there too. In fact most placements there also have a low package. 

As for highest possible package from NIT Warangal or Trichy - this again differs from year to year depending upon the company that has come to recruit. You could check the placement statistics of NIT Warangal or Trichy, ask some alumni for details. This will allow you to get an idea.