You can check the top NITs for mechanical branch below

1- National Institute of Technology, Tiruchirappalli

According to their Reports Placement Percentage in Mechanical branch (2016-17)- 98.5

You can check the placement detail from the given below link

NIT Trichy Placements

2- National Institute of Technology, Surathkal

According to their reports for the year 2016-17 for mechanical branch total number of eligible students-113 and total number of placed students- 107

You can check the placeent detail from the given below link

NIT Surathkal Placements

3- National Institute of Technology, Warangal

According to their placement report

No. of students registered: 96

No. of students with CGPA>6.0: 86

No. of students placed: 81

Avg. Pay Package (Core industry): Rs. 5.1 Lakh per Annum

Avg. Pay Package (Non-Core industry): Rs. 4.5 Lakh per Annum

Highest Pay Package: Rs. 13. 77 Lakh per Annum (ITC)

4- Motilal Nehru National Institute of Technology, Allahabad

According to their placement report in mechanical engineering

Eligible Students- 109

Placed-93

Job offers-111

% Placement- 85.32

Average CTC (lakhs)- 6.48

Max. CTC (lakhs)- 14

5- National Institute of Technology, Calicut

According to their placement report in the year 2016-17 for mechanical branch

Total Students- 112

Placed-80

Max. Salary- 14.5L

Min Salary-3.4L

Average Salary- 6.8L

Good Luck!!