Hypermiling in an SUV

[Formula413]

One of the vehicles I drive at work is a Ford Explorer. Since I'm the primary driver of this vehicle I've been keeping track of fuel economy and have been able to hit the 20% over threshold for hypermiling on a few tanks so far, and every tank I've checked has been at least 7% over EPA. Most of these tanks have been in colder weather on winter blend fuel, so I'm looking forward to see if I can push it even higher. EPA FE is 13 city, 18 highway, 15 combined. The way it is driven is fairly close to the 45% highway/55% city split the EPA uses.

The specs are: 2002 Ford Explorer, 5 speed automatic, 4 liter V6, automatic 4WD. No ecomods at all, factory recommended air pressure in tires. The techniques I've been using are pretty straightforward. On the highway I never drive faster than 55 mph. When it comes to acceleration, I ran my Scangauge on it a few times to get an idea what different loads feel like, and try to shoot for a load of about 70% when accelerating. The transmission can be coaxed into lockup in OD at about 37 mph, so I try to keep the speed around there whenever possible. One technique I have been concentrating on is braking early when necessary to avoid full stops if possible and conserve momentum. I also put it in neutral at idle and shut it off if I expect to be stopped for more than 20-30 seconds.

One thing I plan to try in the future is accelerating with lighter loads, and trying to coax the transmission into short shifting by lifting. I would like to get an idea of whether the gains to be had from accelerating with load are offset by increased slippage in the torque converter. Also, in the next few weeks it will be seeing a large amount of highway use. I'm not sure if it has summer blend in it yet, if it does I'm hoping to crack 20mpg.

These might not be huge gains here, but it is nice to see that even a not so eco friendly vehicle can at least be made somewhat less so by applying proven techniques.

[UfoTofU]

Keep the up the good work

[1337]

Nice. Would anyone notice if you increased tire inflation?

If you cruise at 55 or 60 on a flat road, what does the Explorer's load look like? I aim never to go over a load of 50 in my Mazda, and usually it cruises at 30-35 load on the highway. If the load drops below 25 on a downhill, I'll push in the clutch and coast.

[Formula413]

Originally Posted by 1337

Nice. Would anyone notice if you increased tire inflation?

No, no one would know the difference, however I'm reluctant to mess with tire pressure on a vehicle with a high center of gravity, I'd be willing to bet the factory recommended PSI was arrived at with an eye toward minimizing rollover risk. And I'm not the only person who drives it, so even if I had more pressure and knew to drive accordingly no one else would.

Originally Posted by 1337

If you cruise at 55 or 60 on a flat road, what does the Explorer's load look like? I aim never to go over a load of 50 in my Mazda, and usually it cruises at 30-35 load on the highway. If the load drops below 25 on a downhill, I'll push in the clutch and coast.

IIRC engine load was around 50 on the highway. I might put the SGII back on it again at some point, but I don't want to take it of my Escort right now as I'm trying to get the calibration spot on. I need another Scangauge. Or two.

[Formula413]

This past Friday I had an opportunity to see what this thing can really do: I took it on a 250 mile round trip, mostly highway with a fair amount of 45-50 mph backroads. The results were impressive: 22.8 MPG, 27% over the EPA highway estimate. I got caught in traffic a few times, were it not for that I might have hit an even 23. The fastest I went was 60 mph on the freeway with a 65 mph speed limit, otherwise I drove pretty much right at the speed limit. And in a humorously fitting twist, I ran across this handsome devil on a winding country road in Connecticut...

[Cd]

Great work Formula413 !
I think a lot of SUV owners would have appreciated some tips from you when gas was more expensive.

I love high gas prices ... it has a very positive change on the way people think about conservation.

Did you have a chance to rescue the turtle ?

[Formula413]

Yeah, it was sitting in the middle of the road so I carried it to the side, it said thanks by trying to bite my hand off. There's gratitude for ya! It's a snapper if you can't tell from the pic. Those jaws make a scary sounding thunk.

I agree on the high gas prices, they aggravate me when I see them going up but then I realize the upside. I remember seeing a story somewhere that estimated how many tons of CO2 were kept out of the atmosphere by this summer's price explosion.

[cfg83]

Formula413 -

You were probably driving too fast for him, so he just ... snapped, .

CarloSW2