[Ankur]

I think so you are eligible.. Although the Gate 2016 eligibility criteria is not out, this is the last year's criteria. These criteria do not change drastically year over year. There are more knowledgeable people on this forum, lets see what they have to say. Before i continue- I really respect your thought of even planning for higher studies despite a break of 5 years.

According to Gate 2015

Before starting the application process, the candidate must ensure that he/she meets the eligibility criteria of GATE 2015 given in Table 4.1. So please study the following table carefully and make sure that your year of qualification is not later than what is specified.

   

Certificate from Principal Candidates who have to submit a certificate from their college Principal, as determined from Table 4.1, have to obtain one from his/her institution beforehand and upload the same during the online submission of the application form. Candidates with Backlogs Candidates, who have appeared in the final semester/year exam in 2014, but with a backlog (arrears/failed subjects) in any of the papers in their qualifying degree should
1. upload a copy of any one of the mark sheets of the final year,
OR
2. have to obtain a declaration from their Principal along with the signature and seal beforehand and upload the same during the online submission of the application form.

http://gate.iitk.ac.in/GATE2015/docs/ib.pdf