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how does my 4x4 work?

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Old 12-03-2009, 10:27 PM
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Default how does my 4x4 work?

ok, i knew that would get some attention. lol but im semi serious.

i have an 09 quad cab sport 4x4. 3.55 rear

how exactly does it work? (mine just has 2wd,4hi,4lo)

i wish i could see an example like on the jeep website, that shows a graphic of how each system works....

would it be similiar to their command trac 2?
http://www.jeep.com/en/4x4/how_syste...ommand_trac_2/

now. does this system put all the power to one wheel etc. on our trucks? or each wheel gets 25% power?
 
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Old 12-04-2009, 08:23 AM
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In 4wd it gets split 50% front 50% rear. It works just like that diagram in your link. It's the simplest system with the least amount of parts to break or wear out.

It will vary the amount of power to each wheel depending on traction. If one wheel has lots of traction, and the other has no traction... all the power gets sent to the wheel with no traction.
 
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Old 12-04-2009, 01:06 PM
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ok, thats basically what i was talking about. so it doesnt "lock" the front. so essentially one wheel can get almost 100% power if needed?

dont most of the hardcore off road guys, want air or elec. lockers? dont those lock the diffs, so all the wheels get split evenly and never change?
 
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Old 12-04-2009, 01:34 PM
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Basically yes. Some run spools which lock the axle together no matter what, some run lockers which lock the axle together soon as there is a difference speed(so when coasting its unlocked) and some run LS which are either clutch or gear driven and will sometimes let the tire with traction spin. So all in all... An open diff 4x4 is basically a 2 wheel drive one up front(lightest tire) one in rear (lightest tire).


Josh
 
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Old 12-04-2009, 02:43 PM
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Originally Posted by jball
It will vary the amount of power to each wheel depending on traction. If one wheel has lots of traction, and the other has no traction... all the power gets sent to the wheel with no traction.
That's not how the 4WD system works on these trucks.

http://www.dodge.com/en/2010/ram_1500/capability/4wd/

From the link
"The 4-HI setting locks both drive shafts for extra grip and pulling power to give you confident handling on slippery, wet and graveled terrain."

The 4WD system on my '01 Dakota worked the same way. Definitely don't engage the 4WD on a dry surface. The "4WD Auto" system works differently though. The differentials aren't locked all the time. They couldn't be.

It doesn't mention how the transfer case works, I assume it splits the torque evenly like the Jeep system, but I'm not sure.
 
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Old 12-04-2009, 02:50 PM
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so we have a the open diff?



i also had an 08 jeep grand cherokee overland. it had this system. awd

http://www.jeep.com/en/4x4/how_syste...uadra_drive_2/

but it had electronic LSD'S front, center, and rear!!

how the hell does that affect that video in the above link?

side note: that thing was AMAZING in ice/snow etc.....
 
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Old 12-04-2009, 03:17 PM
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Unless your truck came with a LSD then yes it is open.

Josh
 
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Old 12-04-2009, 03:29 PM
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You are misreading what they are saying. It splits it thru the drive shafts, not axle shafts. 50% to the front 50% to the rear, if you have no traction on one of your tires - it will send all that power to the tire with no traction and make it spin (unless you have the LSD - which he doesn't with the 3.55 option). I think you are confusing what the transfer case does and a differential.

The 4wd Auto setting that you are talking about is common on some of the older Grand Cherokees and even regular Cherokees, and other Chrysler products that came with them (249 and 242 transfer cases). These transfer cases have some sort of viscous coupler that will send the torque to the drive shaft which has more traction.


Originally Posted by Ironsides
That's not how the 4WD system works on these trucks.

http://www.dodge.com/en/2010/ram_1500/capability/4wd/

From the link
"The 4-HI setting locks both drive shafts for extra grip and pulling power to give you confident handling on slippery, wet and graveled terrain."

The 4WD system on my '01 Dakota worked the same way. Definitely don't engage the 4WD on a dry surface. The "4WD Auto" system works differently though. The differentials aren't locked all the time. They couldn't be.

It doesn't mention how the transfer case works, I assume it splits the torque evenly like the Jeep system, but I'm not sure.
 
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Old 12-04-2009, 03:37 PM
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4hi is 50/50 front/rear. 2hi is 100 rear... 4lo is same as 4hi just lower gearing. if you have one rear tire on the ground and one front tire on the ground you arn't gunna go anywhere. if you have 2 front tires and one rear tire on the ground you can move long as your in 4x4. So all in all the transfer case sends power equally to both axles, which in turn the axles(ring and pinion) differentiate the power to which ever tire is lightest(easiest to spin). So when you put your truck in 4hi you have a 50/ 50 split. even if you have no tires on the ground in the rear and 2 tires up front on the ground only 50% of the power will be applied up front. Idk about the 4 auto with these.

Josh
 
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Old 12-04-2009, 06:38 PM
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Originally Posted by jball
You are misreading what they are saying. It splits it thru the drive shafts, not axle shafts. 50% to the front 50% to the rear, if you have no traction on one of your tires - it will send all that power to the tire with no traction and make it spin (unless you have the LSD - which he doesn't with the 3.55 option). I think you are confusing what the transfer case does and a differential.

The 4wd Auto setting that you are talking about is common on some of the older Grand Cherokees and even regular Cherokees, and other Chrysler products that came with them (249 and 242 transfer cases). These transfer cases have some sort of viscous coupler that will send the torque to the drive shaft which has more traction.
I was under the impression that the differentials lock up when in 4WD, except for 4WD Auto. I'm going to look into it.
 

Last edited by Ironsides; 12-04-2009 at 06:51 PM.


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