Ain’t nobody got 20mpg on a highway on a 200 ever unless it’s straight downhill for 20miles.
I’ve done it many times and obtained 21-22mpg with our 2008 fully loaded.
It’s easy at higher altitude where I live in CO. Several factors are involved such as altitude, air temperature, humidity, tire psi, if there’s added exterior stuff like aftermarket bumpers, if there is no front nor cross wind.
Cold dry air is denser than warm humid air. So I usually get about 17-18mpg in the CO winter than in it’s summer months.
Unlike most American drivers, I don’t quickly accelerate from a stop and I coast into stops. It’s a rare occurrence I’ll push the rpm’s past 3.5k
The only after market parts are a cb radio and antenna. Tires are Yokohama Geolander G015 at 33psi.
I use Mobil 1 Advanced Fuel Economy which has given my Cruiser a slight increase in mpg. I regularly grease the zerks, have a clean engine air filter, change the plugs approx 50k, and change the tranny fluid approx 35k.
Gas octane is the lowest at the pump.
Usually my highway speed is around 70-75.
There’s a sweet spot where going about 70-75 will yield a higher mpg than 50mp.
There have been times I’ve filled up at the TX/NM state line and achieved 21-22mph returning home to Highlands Ranch, CO, going 75mph. I’ve seen 20-21mpg in other states.
- Driving style.
- Weather conditions.
- Altitude.
- After market items.
- Tire type and psi.
- Maintenance.