No issues at all! It hard to get more MPG's out of a light duty truck that can achive 30 MPG stock, but it can be done. The biggest gains you will see are with ECM and TCM tuning, and operating on the highway around 55-60 MPH. This is where we see the extended torque curve and added power let you run a gear higher and lower RPM's. This will result in better fuel effeiciency.