If you are going 85 mph on the interstate, 15mpg seems about right unless you’re drafting a big rig.I really thought I was the only one that thought this. 6th in a JLU Sport S is pointless at 80 on I-95 in South Florida, which is really flat because I find that I lose speed at the slightest incline. 85 is the only time I can use 6th but then my mileage drops below 15 so I have slowed down. Speaking of, am I the only one averaging 15-16 on the interstate? I have Rubicon takes offs and a 2.5 inch lift but in a ton of other threads, I'm seeing people get close to 20.
My commute is on a country road cruising at 60 mph. I consistently get ~20mpg with the hard top on. But as soon as I hit 70-80, my mileage drops off a lot.