Ramasubramanian began work in the 1970s with Tata Motors Ltd (then TELCO). The past few decades have seen Ramasubramanian work for Axles India Limited and head up the Engineering Research Centre at Eicher. He was also Chief of Product Development (1993-2003) at Eicher Motors Limited and Group Head for Product Development for the entire Eicher Group. In 2003, he took over as CEO of Eicher Tractors and later was CEO of Eicher Motors (Commercial Vehicle Unit).