Not any more, they don't. "The 405" (San Diego Freeway) is bumper to bumper nearly all daytime hours.

I've topped 50 mpg sometimes.
Yup. I'm really happy about it, too.
What goes up must come down. I figure it pretty much evens out.

 

In summer after the engine is thoroughly warmed up find a very low traffic flat smooth road where there are no stops, and you can drive slowly. Pull over and stop the car to reset the indicator for mpg since last Start. Start again, make sure it is in ECO, and slowly accelerate up to 30 mph, then put it in cruise to hold 30 mph. Leave it there and short of having an accident, don't touch anything for about 30 minutes (15 miles). Now check your mpg since last start. I got about 70 mpg with this technique. The only problem is that I cannot drive that way.

 

And who the heck can?

 

Me for sure, I couldn't drive at 40 either if I lived in Central California or a large city like Dallas. We do have a little more traffic on our about 9 year old 4-lane highway to town. The extra traffic during the winter is people from El Paso driving up to Apache Peak a snow capped mountain to ski and others are going to gamble at a large Casino near Ruidoso, NM.

 

Most cars (hybrids and non-hybrids) are optimized to get max fuel efficiency at 50-60 MPH. I seriously doubt the THC gets better milage at 30 than it does at 40, or even 50. Most components of the vehicle work more efficiently at far higher speeds, but wind resistance starts becoming very significant above 40, and the optimum efficiency is usually well above 40. With no wind resistance, the peak fuel efficiency would be very near the top speed of the vehicle, at the highest gear ratio and at fairly high engine RPM.

Could you try this experiment again next summer at 50 MPH? It is also important to do it when the wind is near zero, as that has a significant impact on milage, with a headwind hurting far more that the same speed tailwind helps. Also, the acceleration should not be too slowly, just not briskly. A fair acceleration does a great job optimizing the mix of electric and gas where a too slow acceleration inefficiently uses the electricity alone too much.

-- Alan

 

It will be interesting when it warms up in Tempe you can compare your years of driving the '07 TCH to your new ES hybrid. My comparison is 8 mpg gain with the new '12 XLE TCH. Yours may be less due to the larger body. I don't know the reason but my winter driving so far is matching almost exactly what I got in the '07. I been asking my wife did we used to go to town a hour or two before dark. During the winter the temperature drips 10 degrees or more when the cold air slides down the nearby mountains into the desert valley. Now we go a hour after dusk when it's colder due to my wife sleeping all day.

Not long after we married I thought she might be a vampire. She always liked working jobs on deep nights and then sleeping when the sun comes up. We retired in the mid 90's, but she won't change. I have to stay up all night just to see her. lol

 

Unfortunately, my driving patterns have changed. My wife's new job is only 2 miles from home, resulting in expected poor numbers. Comparing computer reported tanks to measured tanks I get similar differences, where the computer tends to read around 1 MPG higher than my hand calculator. Comparing very familiar drives I have done dozens of times in both cars, I think the ES tends to be 3-6 MPG higher. However, my overall MPGs so far is about the same, no doubt due to my wife's daily non-warmed up driving twice a day. That is, a normal tank is seeing 36-37 MPH, which is what my TCH did in the winter months with the colder temps and ethanols blends.

-- Alan

 

Ron did his 70 mph test in his '12 TCH. I remember back when my '07 TCH got 52 to 55 mpg combined. The 55 would be during the prime time 85 degree days. (AC off) For comparison I drove each month to see a foot doctor in Las Cruces about 85 miles away. I got 48 mpg highway driving at 60. My guess would be 50 or 51 if I drove at 50.

This may not be a good comparison as the 52 to 55 mpg was combined driving at then 44 mph with the ice and 35 to 40 on EV when in town.

Alan you mentioned something about gas mileage in a gas powered car. I read in a very old popular mechanics book that 48 mph was the best speed for peak mpg. That has not changed much. My wife had a '99 Ford Ranger pickup that got 27/28 mpg during the summer. Later she bought a 2010 Ranger and now that it's broke in she gets 29 to 30 mpg. She always drives to town at 46 mph, (calculated) then makes 3 or 4 stops in town. It was 27 to 28 with the 2009 model. The '10 has a tachometer so she watches for the overdrive to kick in when the engine drops 200 to 300 rpm.

Now that the engine is broke in on my '12 TCH this Summer I can try driving at various highway speeds and see the mpg difference. So far both the '07 and the '12 seem to get their best mpg at 43 to 44 mph.

 

Coefficient of drag on a pickup is far higher than in a modern sedan, so optimum efficiency will be at a slower speed due to more pronounced drag on the pickup.
Quite possible, but I would guess the best MPG is closer to 50 MPH. Just watching my instantaneous milage at various speeds over a couple miles with cruise control suggests to me a peak very near 50. Of course, I always get the max 60 MPG in EV mode, but that is just borrowing energy from non-EV driving, and will always be a net loss for a hybrid.

-- Alan

 

Your right, any pickup is like a plow into the wind. The tailgate up is similar to a parachute other than the cab may block off some of the wind. I have no idea how my wife gets the rather high mpg with her pickup other than the new one has the same new engine as the '10 Focus.

Alan I see you name reminds me of the many phone calls in the past talking to Linear Logic techs in Mesa, the ScanGauge people. I would set the SC to default so I could then read a higher mpg number, which made it easier to determine which speed gives me the highest peak mpg. I would then look at to see the instrument panel and now navigation screen to see what the mpg actually is.

So far with the '12, driving at 40 mph I get around 50 mpg if the traction battery is fully charged. If it's charging then it pulls me down to 38 to 40 mpg for only mile or mile and a half. The charge time varies from summer to winter. It seems like winter takes longer for it to charge.

I have sped up to 45 which the mpg seems to hold about the same. Going up to 50 the mpg seems to drop more than I like. I think it's more the increase in headwind. I do these test when their is no wind on my wx station at my house before heading the 8 miles to town around 6:30 pm.

I still can't see why they don't heat the intake air by using the heat off of the exhaust just to help the mpg some. Maybe a quick switch to a cool-air intake for quick acceleration. A car (gas or other) driving along in 15 to 20 deg air don't get the same good mpg as one driving in 75 to 80 deg air.

Earlier I was looking at a scan gauge mounted using two sticky back (black) rubber pads. I use the velcro strips that comes with it but sometimes it tilts some to the right. Anyway I found I can use a small bottle of swim-ear bought from any pharmacy to soak the velcro and it will lift right off after a minute, even after being cooked on over many hot summers.

Jimmy