So I just wanted to share 2 upgrades that got me from 8 mpg to 12-14mpg average with both upgrades.
1 I have an aftermarket boxed cold air intake
(AFE cold air intake for 5.7l)
2 PowerMax Chip for 5.7
These 2 upgrades helped me gain more mpg and saved some gas.
I get 89 fuel and used to last only 3 days max with my daily driving before another fill up now I have almost a day and a half extra!!