Now that my engine is broken in with over 1,700 miles, an oil change, and a tonneau cover, I try a highway MPG test again to see if those factors make a difference in MPG on the new 6.6L L8T gas engine with 10speed Allison transmission. If you didn't catch my original MPG run, check out this video here:
   • MPG Test // I Drive 400+ Miles with M...  

00:00 Intro
03:15 Why is MPG All Over the Place?
07:43 Updates
12:51 MPG Results

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