One of the major factors in my fuel consumption is idling in the winter.

I manage a number of jobsites, and circulate between them throughout the day; in the winter I leave the truck running most of the time.

I've driven and would be happy with the performance and consumption of either the 5.0 or 3.5EB engines, and I'm wondering if the EB would burn less fuel at idle, all else being equal? Six cylinders vs. eight seems to make sense, right?

 

I think your assumption is correct; the smaller engine will consume less fuel when idling.

 

Yes. Smaller engines use less fuel at idle.

Source: Tune engines with AEM EMS

 

Are the twin turbochargers in the Ecoboost engine fed by engine oil for lubrication?

With most turbocharged engines, you don't want to shut them down immediately after a heavy load. The best practice is to let it idle for a while to let the turbo cool down, and the lubrication to circulate. So it may be better to let such an engine idle instead of turning it on and off more often.

 

My question would be how does the fueling system and turbos on the EB handle extended idleing? We already know how a 5.0l type system will handle it. If someone here has a Scangauge II they can give you an idea of what the GPH is on either engine. The lowest reading I've seen on my 6.8l is .60 GPH in N with nothing but the radio on but .66 GPH is the norm.

 

The Ecoboost turbos are both oil cooled (like a traditional turbo setup) and water cooled (unlike a traditional turbo setup). The engine coolant will continue to circulate after the truck is shut down. Due to this, it is not necessary to idle an Ecoboost engine for an extended cool-down.

 

Buy an elm 327 bluetooth adapter and get the torque app (assuming you have an android smartphone) and it will tell you all the information the ECU is reporting via the OBD2 port.