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4A vs 4h (4x4 knob)

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Old 07-17-2017, 07:16 AM   #11
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Is one version tougher/better? Seem the same? Meaning is one 4x4 system preferred?
Subjective answer.

Since they are not the same, they cannot seem the same.

Usage as explained by zx12-iowa.
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Old 07-17-2017, 09:22 AM   #12
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4A always applies power to all 4 wheels when accelerating from a stop. It cuts back to 2WD at cruising speeds. But with 4A, you'll never lose grip when leaving a stop sign when it's wet. I use 4A in the rain and in winter.
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Old 07-17-2017, 09:41 AM   #13
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Is one version tougher/better? Seem the same? Meaning is one 4x4 system preferred?

This is essentially what is in the lariat and above trims, this would probably be the system prefered by most as its the most seamless. Basically in 4x4 auto the truck locks the front hubs and pushes power to the front wheels as needed, allowing some slip.

Last edited by funnyman06; 07-17-2017 at 09:57 AM.
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Old 07-17-2017, 11:07 AM   #14
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The variants with 4A have a different transfer case because there is a clutch to allow for slip between the front the rear axles, not a differential.

Our trucks have a differential between the rear tires instead of a clutch because a clutch isn't a long term solution to allowing two outputs to spin at different speeds. It will prevent binding of the drivetrain by allowing them to slip, but it will overheat with too much use.

The owner's manual, on page 186, doesn't distinguish between 4H and 4A when saying that one shouldn't use four wheel drive on dry, hard, roads. Earlier it allows for 4A on all roads though. It is therefore inconsistent, but the system remains a part-time 4x4 in architecture because there is no center differential. A clutch doesn't change that.
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Old 07-17-2017, 11:30 AM   #15
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It's actually possible to drive in snow in 2WD.
Don't I know it, drove a 2wd ranger for 10 years

get out the sand bags and HOPE you don't get stuck as a light on an incline. Fishtailing is fun though.

The reason I was asking if one was preferred is because after this lease I will most likely purchase a lariat or above.

so there hasn't been much discussion over the 2 4x4 system (like there is over the motor choices) so it probably doesn't matter that much.

Other than towing scenarios, I will most likely use 4x4 a handful of times a year, and mostly for side streets that aren't plowed yet. It would be nice to leave it on something like 4A and just let the computers determine when and where power is needed.
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Old 07-17-2017, 11:34 AM   #16
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Subjective answer.

Since they are not the same, they cannot seem the same.

Usage as explained by zx12-iowa.
I would say the engine debate is a subjective answer and yet folks don't seem to have a problem with an opinion lol.

I think it is good news there isn't a debate here, that means that both work well and there hasn't been a need to much of a debate. I'll consider it a non-topic until I read differently....
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Old 07-17-2017, 11:36 AM   #17
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Did you watch the video? the 4x4 in the higher models is a much "better" system. The rest of us get a tried and true basic 4x4, this will break things if used incorrectly.

Borg Warner TOD however has been around for many years, Isuzu used it a bunch as well.
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Old 07-17-2017, 11:40 AM   #18
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Did you watch the video? the 4x4 in the higher models is a much "better" system. The rest of us get a tried and true basic 4x4, this will break things if used incorrectly.

Borg Warner TOD however has been around for many years, Isuzu used it a bunch as well.
I did, I get what you are saying, my next truck will be a lariat or higher so I will end up with 4A.

Just as with the turbo vs NA debate, I might argue that the auto system has more stuff to go wrong, or it would see so, so I would expect more failures

But as with the motor debate, we really don't know unless we see ford data.

I'll just limit the use of 4H unless needed. I would probably use 4A more (leave it on for trips to the store in the snow)
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Old 07-17-2017, 11:45 AM   #19
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fun facts about modern 2wd trucks, and just trucks in general:

1) Traction Control Systems designed to actually work properly

2) LSD/Lockers

3) overall weight is much heavier than previous model trucks, especially a modern half ton truck vs something like a 90s ranger

In an old school setup, where both axles are open diff, you have ONE tire on each axle getting power. So your 2wd/rwd is really a 'one wheel peel'. Your 4wd only has 2 wheels turning at any time. Now this is where the magic happens...

With a LSD or TCS that mimics one, both of your rear wheels are turning at the 'same' time, thus you have 2 wheels fighting for traction to push you forward, not just the old school one where either tire was on a slick surface and instantly stuck. Yes, back then it was impossible to drive a 2wd truck in bad conditions. But in todays world, both tires pushing you forward, 90% as good as an old school 4wd situation.

The advantage to the 4wd system though, separation of axles, so if your rear is compromised, your front can pull you to help get your rear going again. The Front drive is almost always used to simply 'help' your rear axle gain traction, and that's only real purpose in most situations.

I think people have a really flawed understanding of how 4wd trucks work in general. Now if you live in the mountains with serious grades and harsh winters, obviously a 2wd truck is going to be stupid for you. But thats not the case for most people, people in the DC metro area think you CANNOT drive a 2wd truck in snow 3ft without getting stuck, but yet they think a prius is totally fine.

to the OPs question: as everyone said, the 4A is really just a luxury item. Its going to put you in and out of 4H when it thinks your rear axle needs the additional assistance of the front. Personally I dont like them because I like to be positive control of whats happening, I don't like the instant steering change of hopping in and out of 4wd especially on a winter road. Thats just me, alot of people love it and if you have a spouse or kids or whatever, someone who isnt a 'truck driver', the 4A really shines for them. Or even if thats you, the primary driver, just want to get in and go its a good feature to have.

I'm not sure I would use the word better, but its definitely a nice safety feature for some drivers/situations.

Last edited by SilverSurfer15; 07-17-2017 at 11:54 AM.
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Old 07-17-2017, 11:53 AM   #20
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Originally Posted by SilverSurfer15 View Post
fun facts about modern 2wd trucks, and just trucks in general:

1) Traction Control Systems designed to actually work properly

2) LSD/Lockers

In an old school setup, where both axles are open diff, you have ONE tire on each axle getting power. So your 2wd/rwd is really a 'one wheel peel'. Your 4wd only has 2 wheels turning at any time. Now this is where the magic happens...

With a LSD or TCS that mimics one, both of your rear wheels are turning at the 'same' time, thus you have 2 wheels fighting for traction to push you forward, not just the old school one where either tire was on a slick surface and instantly stuck. Yes, back then it was impossible to drive a 2wd truck in bad conditions. But in todays world, both tires pushing you forward, 90% as good as an old school 4wd situation.

The advantage to the 4wd system though, separation of axles, so if your rear is compromised, your front can pull you to help get your rear going again. The Front drive is almost always used to simply 'help' your rear axle gain traction, and that's only real purpose in most situations.

I think people have a really flawed understanding of how 4wd trucks work in general. Now if you live in the mountains with serious grades and harsh winters, obviously a 2wd truck is going to be stupid for you. But thats not the case for most people, people in the DC metro area think you CANNOT drive a 2wd truck in snow 3ft without getting stuck, but yet they think a prius is totally fine.

to the OPs question: as everyone said, the 4A is really just a luxury item. Its going to put you in and out of 4H when it thinks your rear axle needs the additional assistance of the front. Personally I dont like them because I like to be positive control of whats happening, I don't like the instant steering change of hopping in and out of 4wd especially on a winter road. Thats just me, alot of people love it and if you have a spouse or kids or whatever, someone who isn't a 'truck driver', the 4A really shines for them. Or even if thats you, the primary driver, just want to get in and go its a good feature to have.
My Ford Ranger was purchased new in 1994, and that was tough to drive in bad conditions, but I got through it.

It would seem all of that shifting in and out of 4H would wear things down quicker, I wouldn't use it enough to be an issue.

here in Rochester we get 120 inches of snow a year, lots of time to get good at driving in snow.

The good thing about Rochester is most know how to drive in the snow, unlike DC where people freak lol
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