In December 2012, the Trinity Metor Board approved use of diesel multiple unit (DMU) vehicles for the TEXRail project. Diesel-powered vehicles will meet strict federal emissions standards. This technology is NOT light rail as seen in the DART system, which depends on overhead electric power. Instead, this proposed system uses self-powered rail vehicles, which would be significantly less costly than electrified light rail.
In June 2015, Trinity Metro signed a $106 million contract with Stadler Bussnang AG for the manufacture and delivery of eight DMU rail vehicles for its TEXRail commuter rail.
The trains will seat 229 passengers and have hand rails for standing passengers. The new trains will have level boarding meeting the ADA requirements. There will be four entry points on each side of the train for easy access.
In addition, the DMU rail vehicles purchased are significantly quieter than the previous option. The previous train option would have required mitigation along the route because of the noise, such as sound walls. The DMU option does not require mitigation because the DMUs are so quiet.