I rented a Suburban that had cylinder deactivation. The highway MPGs were 21ish if you could maintain a constant speed. You get stuck in traffic and bye bye gas mileage. Stop light to stop light it was ok. Merging on the highway or trying to make lane maneuvers were all but impossible, unless you just cut people off. You'll find yourself flooring it just to make it go.

 

That sounds NFG. our 3.5L EB is very, very driveable. Sweet ride in fact. The only difficulty (for me) has been using the automatic transmission in the mountains. Even using tow/haul or sport mode, it was always reacting late, and with too much "enthusiasm". I got exactly the reaction I needed by shifting into manual mode, and selecting the gears myself.

 

My wife has a minivan with cylinder deactivation that seems to work pretty well. You get some vibration in the wheel when it goes down to 4 cylinders, but overall driveability is good and it seems to make a dent on fuel consumption.

On the video referenced earlier in the thread, we monitored my temperatures with an OBD reader and the Torque Pro app. Max coolant temp was 243 degrees.

I don't think this has anything to do with it. To my knowledge the PID data for coolant temp comes from a coolant temperature sensor. So if the coolant temp hit 243, the system had no trouble moving heat from the engine to the coolant. The bottleneck was with heat being rejected from the radiator into the outside air. If your theory were correct the oil and head temperatures would have risen while coolant temp didn't. I have no evidence to support that idea.

The radiator size difference is noticeable though. As per the Ford specs the EcoBoost/Max Tow radiator is 521 square inches. The Super Duty 6.2L radiator is 837 square inches, and benefits from a clutch-driven fan that's far more powerful than the electric fans in the F150. The 6.2L doesn't have to worry about cooling the exhaust system, and the EcoBoost's cooling system has to absorb heat from two glowing hot turbos.

Combine slightly smaller radiator with increased power at a given RPM, a less effective cooling fan, and the added heat load from the turbos, I think it's pretty clear why it got a little warm.

 

The mass of the engine does not just have more area for transferring heat to the cooling system and oil it also takes more heat to get it up to a higher temperature vs say the EB. Then when you get down the other side of the grade you have more cubic inches to pump fuel and air thru to cool the engine down.(because that what these engines are, air pumps) You also have more cubic inches to increase engine braking. There is a reason why trucks and equipment that are made to carry heavy loads throughout their lives use rather large displacement engines vs a smaller displacement engine that is capable of the same output. Many of the people in this thread seem to think just because an engine makes the same or more power than a larger engine, that the smaller engine is suitable for the same applications. Which is false.

 

Can't argue with any of that.

 

Wife's V6 Honda SUV has cyl deactivation & it works flawlessly. From a driveability standpoint I don't notice it kicking on or off.

 

I do get the point you made though.

My hunch is that the actual coolant temp before going to the radiator in the case of the 3.5l EB in the test was less than 243 degrees. I say this because the temp sensors are usually fairly close to the heat generating areas of the engine, plus they are usually screwed into aluminum or iron.

On a lighter and more aerodynamic SUV I don't doubt it. Trucks on the other hand are not what I call either.

Honestly I would rather Ford stay away from cylinder deactivation. Their mpg are close enough to the competition as is.

 

My money is on the 6.2 about 10 fold.

 

If cylinder deactivation worked well, maybe Ford would use it, but it doesn't.

The internet is full of devices like this to deactivate the GM fuel management system and keep your V-8 working as a V-8. If the strategy worked well, there would be no market for these devices.


Typical review of this device:

Used on a 2009 Suburban, that is substantially used for highway travel. Having the AFM disabled has not decreased fuel mileage whatsoever. This suburban was using oil due to the AFM (approximately 1/2 to 1 quart in 3,000 miles) and this is the only device made that can disable AFM without a tuner. After using it non-stop for approximately 4,500 miles - THE OIL USAGE HAS STOPPED - PERIOD! I just checked this morning and the oil has NOT budged. (2009 Suburban 36,500 Miles).

 

You can't rip a single example of a bad system out of context and declare them all to be ineffective.

The system in my wife's Honda works great and seems to get about 3 MPG better than competing vans on the highway. Chrysler has been using cylinder deactivation for about 10 years, and starting a couple of years ago they were putting it into their heavy duty pickups.

 

June 17, 2014 my truck got destroyed and I rented another truck for work. It was the 5.7l Ram. I couldn't tell when it kicked in and out of 4 cylinders. Ford was out of production and I almost bought a Ram. It just didn't feel right.

Anyhow, I was impressed the the Ram.

 

It's too bad that you didn't buy the Ram, then you could be over there poking their users with same rhetoric.

 

Too late, Tim. Ram dealer banned him too.

I tried to rep you for that hilarious post.... But it won't let me.

 

From reading 5 pages of this thread, no one ever did mention that the 6.2L has/had 411hp and 434 lb-ft of torque in the F150/Raptor. Ford and Ram tune down their engines from the LD to their HD series pickups. Ram tunes down their 5.7L hemi and Ford does similarly with their SD's. Even Chevy's 6.0L is low in power on paper, but still pulls descent. I'm sure that there's a difference between the same motors such as different cams, timing, tune, and possible transmissions. The light duty trucks are tuned to be sports cars while SD trucks are tuned to work.

 

I sort of mentioned it back in post # 42 of this thread.