Well, after three 5.7s I've found that idling and start/stopping these engines really hurts fuel mileage. Even in wintertime I only idle from a start no more than a minute and progress slowly down the road until I see 100 F. oil temp. Fortunately with the 3.21 axle ratio engine RPM stays under 1200-1300 at my local speed limits.
I also do a lot of driving and most of this trucks life has been spent with the wheels rotating, either country roads or four lane. It does see some city driving once or twice a week, but even then I time traffic lights to keep moving. (If you stop on West Ridge Road in Rochester you better have some body armor on!)
Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33-gallon fuel tank, factory dual exhaust, 18” wheels. Build Date: 3 June 2018. Now at 88643 miles.