Need tutorial on how the 4x4 system works...
04-24-2018, 05:33 AM
#11
I knew someone else would offer up a good explanation and I thanked him for that. I just want to be sure the young'uns and newbies who think they have 4 wheel drive are enlightened because once upon a time in a place far far away, I thought I wanted a 4WD and was enlightened by a smarter person then decided I didn't need it, that a limited slip rearend was just about as good.
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Age_Of_Consent (04-24-2018)
04-24-2018, 06:50 AM
#12
Turbo --> :-)
That and 50 cents will get you a cup of coffee. Used to anyways.
I knew someone else would offer up a good explanation and I thanked him for that. I just want to be sure the young'uns and newbies who think they have 4 wheel drive are enlightened because once upon a time in a place far far away, I thought I wanted a 4WD and was enlightened by a smarter person then decided I didn't need it, that a limited slip rearend was just about as good.
I knew someone else would offer up a good explanation and I thanked him for that. I just want to be sure the young'uns and newbies who think they have 4 wheel drive are enlightened because once upon a time in a place far far away, I thought I wanted a 4WD and was enlightened by a smarter person then decided I didn't need it, that a limited slip rearend was just about as good.
Where do I get that? From my 15 years offroading in many different terrains, and doing experimentation in 2WD and 4WD.
On loose surface, in 4X4 the front pulls and the rear pushes and the truck goes forward in straight line.
In 2WD/locked diff, the front wheels don't turn (no traction) so the are making a resistance to movement. The rear ones push, then the truck will fishtail
About the citation that a 4WD with open diff is a 2WD only, it is true ONLY in certain difficult terrain situations, where one font and one rear wheel are unloaded from uneven terrain. All the rest of the time, like going uphill on dirt, all 4 wheels are touching the ground with a thousand pound on them, and the truck has traction on the 4 wheels.
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bambbrose (04-24-2018),
Florida_F150 (04-24-2018)
04-24-2018, 07:14 AM
#13
Another reason U.S. doesn't want Canada.
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mbrick (04-24-2018)
04-24-2018, 08:34 AM
#14
[QUOTE=arum81cake;5750615]As a newbie to this forum, I was wondering when someone would be...
Oh, sorry... I guess I stepped into your trap.[/Q
Aw suck it.
Newbies better get senses of humor here. 
Code:
a-hole.. ˈāˌhōl/ noun NORTH AMERICAN vulgar slang noun: ahole 1. a person's anus. 2. a stupid, irritating, or contemptible person.
Aw suck it.
Newbies better get senses of humor here.
04-24-2018, 08:47 AM
#15
Turbo --> :-)
[QUOTE=UncleG;5750678]
Well, I'm not a newbie, and I also have a sense of humor, but honestly, I don't see where is the joke, explain please so I can laugh also.
BTW, can you tell me what is your offroading and 4X4 experience. Crawling sidewalks at the mall doesn't count.
As a newbie to this forum, I was wondering when someone would be...
Oh, sorry... I guess I stepped into your trap.[/Q
Aw suck it. Newbies better get senses of humor here.
Code:
a-hole.. ˈāˌhōl/ noun NORTH AMERICAN vulgar slang noun: ahole 1. a person's anus. 2. a stupid, irritating, or contemptible person.
Aw suck it.
Newbies better get senses of humor here. Well, I'm not a newbie, and I also have a sense of humor, but honestly, I don't see where is the joke, explain please so I can laugh also.
BTW, can you tell me what is your offroading and 4X4 experience. Crawling sidewalks at the mall doesn't count.
04-24-2018, 08:57 AM
#16
Member Junior
<<On loose surface, in 4X4 the front pulls and the rear pushes and the truck goes forward in straight line.
In 2WD/locked diff, the front wheels don't turn (no traction) so the are making a resistance to movement. The rear ones push, then the truck will fishtail >>
Well, maybe. But mainly, at speed, the RWD locked/welded diff vehicle will understeer as the locked rear will push the front ahead and want to go forward and not turn.
That is true until you learn how to drive it, and toss the vehicle. This allows a relative consistency in handling dynamics, that the driver can feel confident of what the vehicle will do from turn to turn at speed. Once the vehicle is adjusted to account for a locked rear end (say, disconnect front sway bar, etc) and the driver gets it, a RWD locked diff vehicle is pretty dang good once speed is attained.
Now for slower stuff and heavy off roading, 4WD in it's many forms, is a better solution for success.
In 2WD/locked diff, the front wheels don't turn (no traction) so the are making a resistance to movement. The rear ones push, then the truck will fishtail >>
Well, maybe. But mainly, at speed, the RWD locked/welded diff vehicle will understeer as the locked rear will push the front ahead and want to go forward and not turn.
That is true until you learn how to drive it, and toss the vehicle. This allows a relative consistency in handling dynamics, that the driver can feel confident of what the vehicle will do from turn to turn at speed. Once the vehicle is adjusted to account for a locked rear end (say, disconnect front sway bar, etc) and the driver gets it, a RWD locked diff vehicle is pretty dang good once speed is attained.
Now for slower stuff and heavy off roading, 4WD in it's many forms, is a better solution for success.
04-24-2018, 09:01 AM
#17
Member Junior
Having said that, I am very interested in the OP's request about the technical aspects of our trucks. Thank you. This is more interesting than some app for ordering pizza or whatever from the cab---which it seems the owners manual is more interested in than real technology.
04-24-2018, 09:33 AM
#18
For an XL/XLT, when you turn the **** to 4 high an actuator in the transfer case moves to engage the front output and spin the front driveshaft. At the same time a vacuum solenoid under the hood engages both front hubs (integrated wheel ends in Ford speek). Power is split evenly front and rear with no differential action, so use only on loose surfaces. When you select 4 low a shift fork moves a set of gears in the transfer case to enable more gear reduction. You have to be going slow and in neutral to let it engage smoothly.
On lariat or higher trucks they use a set of clutches on the front output of the transfer case to send power to the front diff. In 4 auto the computer uses sensors to decide when to engage and when to disengage, allowing use on pavement without binding or other wear. In 4 high lock the clutches engage and stay engaged, for all intents and purposes acting the same as the lower level trucks. Same with 4 low. These trucks have the same vacuum actuated IWE setup as the XL/XLT.
All can be combined with an electronic locking rear diff that will send power equally to both rear wheels at lower speeds, automatically disengaging at higher speeds.
The rear transfer case output is always physically connected unless you select the neutral position on the tc, and this is only used for towing behind an RV.
On lariat or higher trucks they use a set of clutches on the front output of the transfer case to send power to the front diff. In 4 auto the computer uses sensors to decide when to engage and when to disengage, allowing use on pavement without binding or other wear. In 4 high lock the clutches engage and stay engaged, for all intents and purposes acting the same as the lower level trucks. Same with 4 low. These trucks have the same vacuum actuated IWE setup as the XL/XLT.
All can be combined with an electronic locking rear diff that will send power equally to both rear wheels at lower speeds, automatically disengaging at higher speeds.
The rear transfer case output is always physically connected unless you select the neutral position on the tc, and this is only used for towing behind an RV.
04-24-2018, 09:52 AM
#19
Senior Member
04-24-2018, 10:17 AM
#20
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Ya, what's wrong with Canada? 4X4 works the same there as in the U.S. At least the last time was there. Guess it could have changed. The weather always stops at the border too, so, I don't know.