Auto 4wd
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I understand. But 4A is basically an on-demand AWD system since 100% of power goes to the rear axle unless slippage occurs (or low speed straight line acceleration). (Yes, i know that it has a TC with 4Hi and 4Lo.)
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Joined: Jan 2022
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From: Evansville, IN
Because road conditions can change very quickly. Oil slick on the road? Puddle on the road? I have construction on the highway i drive.
My point above is that on-demand AWD is reactionary. It is not proactive. It is always late to the party a few milliseconds or longer.
As for WOT, i was testing what above poster wrote about WOT and front axle engagement. I tested it. And it turns out to be false with my truck.
My point above is that on-demand AWD is reactionary. It is not proactive. It is always late to the party a few milliseconds or longer.
As for WOT, i was testing what above poster wrote about WOT and front axle engagement. I tested it. And it turns out to be false with my truck.
when i think of AWD, i think of my wifes edge, kicks in when it senses slippage of the rear wheels, completely seamless, no hubs to lock in, just a transfer case that starts sending power to the rear axle
Most newer F150s with 4A don't have locking hubs, when wheel slip is sensed or predicted, the TCCM increases the duty cycle of the transfer case clutch and sends power to the front axle. This is basically the same way my wife's AWD Nissan operates. In her car, there is an "electric controlled coupling" in front of the rear differential, her car lacks a low range and 2H when compared to my F150. Her sister's Nissan uses a system that operates in the same manor, but in that car the system is marketed as 4WD. The TOD transfer case in my F150 also allows me to drive on dry roads and send power to all 4 wheels without binding, just like my wife's AWD Nissan when I select 4A.
When I think of 4WD, I typically think of a transfer case with low range and binding in turns that prevent use on dry roads, I also think of a system that can be fully turned "off" by selecting 2H. When I think of AWD, I typically think of a system that is always "on", a transfer case/transmission with a center differential or a clutch/coupling that always distributes power to the front/rear axle so that the system can be used on dry roads without binding. "Full time 4WD" systems often seem like hybrid systems that fall somewhere in between a traditional 4WD system and a traditional AWD system.
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From: Sacramento, CA
Our 4A transfer case is kind of a hybrid between a 4WD system and an AWD system. What we have to remember is that the more the TC shifts torque toward a 50/50 split between front and rear, the more it's going to behave like a normal 4WD system and not tolerate different rotation rates between front and rear shafts. At a 50% split, I would be very surprised if the system tolerates any difference in rotation rates. 4A is great for giving it all the beans in a straight line launch but the TC would really hate turns (left or right) under that much load.
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I don’t understand the need to say that 4A mode is something other than a on-demand AWD. Yes, it has transfer case with 4Hi and 4Lo. But in 4A mode, it is basically a rear-bias AWD type system…and literally acts like any other on-demand AWD system.
And apparently, there is a lot of misunderstanding about how this system works. I doubt that my F150 is broken nor an outlier in how it works in 4A.
Just FYI…from reading the internet, if we do indeed have BorgWarner 4417 TC, then it is an old as heck design!
4417 came our around 2007. It is pretty much the same as the 4416, but includes a default off-road program. 4416 came out in 2003.
So, basically, it is a 20+ year old TC design!
Before we crap on Dodge……but the newer Ram uses BW 48-11, which came out in 2019. So unless BW has tradition of making their TC worst over the years, Dodge Ram TC is probably just as good, but likely better than our 4417.
And apparently, there is a lot of misunderstanding about how this system works. I doubt that my F150 is broken nor an outlier in how it works in 4A.
Just FYI…from reading the internet, if we do indeed have BorgWarner 4417 TC, then it is an old as heck design!
4417 came our around 2007. It is pretty much the same as the 4416, but includes a default off-road program. 4416 came out in 2003.
So, basically, it is a 20+ year old TC design!
Before we crap on Dodge……but the newer Ram uses BW 48-11, which came out in 2019. So unless BW has tradition of making their TC worst over the years, Dodge Ram TC is probably just as good, but likely better than our 4417.
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Joined: Jan 2022
Posts: 940
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From: Evansville, IN
I don’t understand the need to say that 4A mode is something other than a on-demand AWD. Yes, it has transfer case with 4Hi and 4Lo. But in 4A mode, it is basically a rear-bias AWD type system…and literally acts like any other on-demand AWD system.
And apparently, there is a lot of misunderstanding about how this system works. I doubt that my F150 is broken nor an outlier in how it works in 4A.
And apparently, there is a lot of misunderstanding about how this system works. I doubt that my F150 is broken nor an outlier in how it works in 4A.
4A is on demand 4X4, ala AWD. 4X4 has 4H and 4L. AWD vehicles have just basically one mode, AWD. A F150 with 4A has 4.
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I don’t care as much about how many modes it has…i care about the mode that i use the most when weather turns bad…4A. For off-road (thus need for 4Hi/Lo), i have my Land Cruiser to take on the challenge…i actually have a decent knowledge about off-road. My Ford is my daily driver…100 miles round trip everyday. That is why i am trying to learn more about 4A to see where the limits are. (This is my 1st Ford product…so my knowledge Ford wise is in its infancy.)