Yeah. I switched to premium fuel half way through Nebraska because the 5.7 was bogging down and struggling to hold 70 and the mileage was just awful - like 5.5mpg awful. Did better after a tank of that, back to cruising 75 and getting Sri d 7mpg. Seems to happen when it’s very hot out (and it was upper 90s to 100 out yesterday).You're certainly making that 5.7L work for a living.![]()
Worked the 5.7 a ton heading over the mountain west of Denver today. Lots of 3rd gear, some 2nd, 4-5k RPMs pretty regularly on the way up. As soon as we got through the tunnel it was 20mph down though as it was POURING rain the rest of the trip