4x4 Auto

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mnachreiner86

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Yeah they are actually, I had video footage of the front CV arms spinning while in 2WD when I was diagnosing a noise I had up front two years ago. It’s called pre emptive on demand AWD. All components move I 2WD from the fluid pressure being loved around in the cases

I tried to shed some light on this too, based on my experience with this system versus the one on my 2000 expedition but got nowhere[emoji2361]. I gave up


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07navi

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I tried to shed some light on this too, based on my experience with this system versus the one on my 2000 expedition but got nowhere[emoji2361]. I gave up


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No light to shed; if the front drive train moves a little from drag (like sunflower kept harping on) it means nothing, but if the front is always turning full speed it will use more HP, tax your acceleration, and put some wear on the moving parts..........not rocket science.
 

chuck s

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You can watch the power distribution to the axles on the dashboard in one of the "off road" screens. In 4A the torque to the front axle is zero (0) in normal driving but gets torque as needed. Yes, you can look at the "off road" screen on the road. Shows percent grades too.

Although technically inaccurate I call this the "Subaru-mode" which my family understands since that's what they drive every day. I can feel the added load on the engine in this mode so only use it in slippery conditions but activate it when the family borrows "my' truck.

-- Chuck
 

Plati

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You can watch the power distribution to the axles on the dashboard in one of the "off road" screens. In 4A the torque to the front axle is zero (0) in normal driving but gets torque as needed. Yes, you can look at the "off road" screen on the road. Shows percent grades too.

Although technically inaccurate I call this the "Subaru-mode" which my family understands since that's what they drive every day. I can feel the added load on the engine in this mode so only use it in slippery conditions but activate it when the family borrows "my' truck.

-- Chuck
It seems like there are so many years and models of Expys that all have different features and user interfaces that any observation only might apply to a specific year/model. It would help if people routinely added that info. I know my 2014EL does not have the feature described above.

I'm impressed by people who say they can hear things and feel things in one mode vs the other and truly believe they believe that. Like "added load on engine". There is no way I'm in that boat. But then again my hearing is going and I guess I'm not perceptive enough to detect a 0.1% change in performance. Kudo's to those who are, but I prefer being able to tune that out and just drive. I'm also not a leadfoot.

I'm under the opinion that the basic operation of the Transfer Case system hasn't changed much if at all since introduction in the 90's, other than user interface and mode control programming. How true is that? Can anyone say "well, in year 2XXX they introduced XYZ operation and it totally changed things. Then in this year that was added etc etc". I know the user interface has changed over the years, thats fairly obvious.
 

07navi

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From Edmunds;

What Is All-Wheel Drive?

As the name implies, all-wheel-drive systems power both the front and rear wheels all the time. But in practice, there are actually two types of drivetrains that are called AWD. One does, in fact, drive all the wheels continuously, and some manufacturers refer to this as full-time AWD. The second, often called part-time AWD or automatic AWD, operates most of the time in two-wheel-drive mode, with power delivered to all four corners only when additional traction control is needed.

How Does All-Wheel Drive Work?
AWD systems, both full-time and part-time, generally operate with no input from the driver, although some offer selectable modes that allow a degree of control over how much power goes where. All the wheels get torque through a series of differentials, viscous couplings and/or multiplate clutches, which help distribute power to the wheels so that the car's traction is optimized. The vehicle still operates smoothly under normal conditions.

Full-Time AWD
In full-time AWD, both the front and rear axles are driven all the time. On dry pavement, this kind of AWD can help the vehicle handle better and ensure that full power gets to the road. And in slippery conditions, such as ice, snow or mud, it provides additional traction for safer, more confident handling.

Part-Time AWD
In normal operation, part-time AWD sends torque to two driven wheels, either the front or rear, depending on the make and model. The system then automatically engages the other two wheels when road conditions demand extra traction. Modern part-time AWD uses an array of electronic sensors that feed information to a computer, which controls the amount of power directed to each wheel.

All-Wheel-Drive Pros and Cons
The best thing about AWD is that the driver doesn't have to make any decisions about engaging the system. Either all the wheels are being driven full time, or the system itself is designed to sense loss of traction and send power where it's needed. AWD is available on a wide variety of vehicles, from compact sedans to performance models to all sizes of SUVs, giving you a broad range of choices.

While AWD is able to work well in a variety of conditions, from rain to snow to light off-roading, it's generally considered a lesser choice by serious off-roaders. This perception is changing somewhat as modern AWD systems get better and more capable, but many drivers who like to venture far off the beaten path still prefer to decide for themselves when to engage four-wheel drive. AWD also increases the cost of a vehicle and, in most cases, will reduce fuel economy.
 

Yupster Dog

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in most cases, will reduce fuel economy.

How many times are you going to say the same thing? Everybody knew your standpoint on the subject your first couple dozen post on the subject.

Anything new to add? Any new viewpoint?

You ever thought the OP wanted input from everyone and not just you?

That is a lot of unnecessary use of the keyboard

You should kick out of ALL USE and go back to just view to keep the mileage off that keyboard.
 

07navi

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How many times are you going to say the same thing? Everybody knew your standpoint on the subject your first couple dozen post on the subject.

Anything new to add? Any new viewpoint?

You ever thought the OP wanted input from everyone and not just you?

That is a lot of unnecessary use of the keyboard

You should kick out of ALL USE and go back to just view to keep the mileage off that keyboard.
Wah wah wah. A little info never hurt anyone. You sound like sunflower but I think she's banned again.
 
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