GMC Sierra 2014 Automatic Gasoline mileage: 300 KM or more Peace, mercy, and blessings of God be upon you. GMC Sierra, model 2014. Converted to 2018 front end, original parts are available. Repainted entirely for cosmetic reasons. I have a video before repainting that proves my statement. I changed its color because the original color was faded, and secondly, I liked the current color on the Sierra. Transmission, engine, and chassis are guaranteed. Any offer less than 55 will not be considered.