Just curious as to what FE the 2012 TCH delivers at constant highway speeds of 60mph, 65mph, 70mph and 75mph.

 

Depending on the time of year (winter gas or summer gas formulations), ambient temps, altitude, brand of gas, terrain, the tires on the car and how much air you have in them, your driving habits and about 50 or so other factors, it will range frpom 20 mpg to over 40 mpg.

Your question is similar to "how high is high" Generally speaking, for most of the people on this board, you will be around 40 mpg @ 60, 38 @ 65, 36 @ 70 and 33 to 34 @ 75.

 

I would agree that is about right, with no wind.

 

I got 48 mpg with the traction battery fully charged on the '07 TCH I had. I have seen around 50 mpg on the '12 TCH but it was not broke in so I slowed back to 55/50/45 mph when the car was very new. This is per some break-in methods I read maybe in the '07 manual.

It very rare I would drive 65 due to the increase in wind resistance on the front of the car. Ron is very correct mentioning without wind. Wind here is usually 5 mph from the SW during most summer days. Their are some months you wonder where the wind went usually from mid Sept to mid October.

 

I got one tank at 42.6 mpg, on I-95 northbound, crossing North Carolina at exactly 65 mph, with a state trooper behind me. I filled up at the first exit in NC, the trooper got behind me on the on-ramp, and he stayed behind me until the last exit before Virginia.

I don't usually do that well on the highway. ;-)

 

Although I been driving my new '12 TCH at 40 mph and slower just to maximize it's gas mileage and EV usage.

The other night I did a experiment due to no cars in site late at night on my side of the 4-lane highway with no-wind. The engine was running and 'charging the traction battery' which was down to about 15%. I started at 25 and 30 mpg, the scan gauge mpg read 35. I sped up to 40 mph and then the scan gauge read 45 mpg. Again I sped up slowly to 50 mph and it still read right at 45 mpg although the wind noise started up some.

I say this, although I have seen 50/53 mpg driving at 50 mph (using cruise & no wind) on a level highway with the traction battery fully charged. Charging the traction battery back up with MG1 and especially MG2 puts a pretty good load on the engine, even at 40 mph.

Anything above 40 speed the wind resistance would become somewhat of a problem, although that would be more like when entering and inside a city speeds.

At highway speeds add in a 5 to 10 mph head wind which would take a 60 mph driving speed to 70 without the car going any faster. Driving at 70, add a 10 mph headwind would be like driving at 80.