GMS Racing promotes Cohen after he worked with Ben Kennedy in the Camping World Truck Series, earning one win (Bristol) and a berth in the inaugural Truck Chase.
In their seven Xfinity races together, Gallagher and Cohen earned one top 10, finishing eighth in the Firecracker 250 at Daytona.
“I am looking forward to the 2017 Xfinity racing season and working with Spencer again,” said Cohen in a press release. “He showed a great deal of growth and performance gains on the limited Xfinity schedule last year as well as the speed he displayed late in the season with the truck. We are excited for the challenge the series brings and will be preparing diligently in the off-season to start strong, be a consistent competitor, and work towards the goal of getting Spencer in the Chase. GMS has taken a great steps in setting us up for success in 2017.”