HOUSTON, Oct 22, 2014 (BUSINESS WIRE) — Nat G CNG Solutions announced today that it has delivered the first natural gas half-ton pickup trucks with General Motors’ 5.3 liter direct injection engine. The 2015 model vehicles were purchased by local Houston company NewTex Plumbing and San Antonio-based Pioneer Energy Services. GMC Sierra and Chevy Silverado trucks for each fleet were upgraded to run on either natural gas or gasoline using the new DuraDrive DI natural gas system, supplied by Utah-based AGA Systems.