Ya i talked to a guy from JDM an he said they have a programer that will disable traction and stability controls 100%...

 

Programmers + warranty = headaches!

 

Thats one of the problems^^^. The system is so integrated into the many electronic systems that effectivly eliminating it has to be a complex task.

 

I am not a mechanic, not even close, and now, after reading all this, I am even more confused.
My thinking before reading all this was:
1. An open differential only provided power to one wheel.
2. A locked differential (posi-traction) delivered power to both wheels.
3. A limited slip was a bit of both. It would act as an open differential until under certain conditions it would lock and act like posi-traction.
Now I did read my manual when I bought my FX4. I just interrupted it differently. I thought it was saying that it works as an open differential under normal conditions, but locks when certain conditions are met, such as one wheel beginning to turn significantly more than the other. I also understand that in 4x4 you can lock it in, where as in 4x2 it would only lock in when those certain conditions are met.
Were my original assumptions wrong or am I reading the manual wrong, or both? I did think I had a limited slip differential until reading all this.

 

REMEMBER IT KICKS OUT AT ABOUT15 MPH, MINE ISNT WORKING AT ALL 09 FX4

 

ALSO WHAT IS THE BIG DEAL ABOUT TRACTION AND STABILITY CONTROLS AND WHY WOULD YOU GET THEM DISABLED IF U COULD

 

Posi traction is actually a brand name for a limited slip sytem... In fords it is called trac loc.

 

Aaha...that helps, and I am not a bit suprised my origional assumptions were flawed. I have found that a lot of my assumptions are flawed, and it's not improving much with age.
Thanks.

 

Never had any problems with my warranty when I had my programmer in my 2004 F150.

 

My dads 1967 GMC had "Posi-traction" which is actually limited slip. You need to be careful with limited slip differentials If you jack up one wheel and spin it under power you will drive off the jack stand, my dad found that out when he changed a tire on his truck and dropped it off the jack, and he had a camper on it at the time, broke a few dishes.

 

TADA!!!! well I think I am gonna answser my own question that I originally posted starting this thread. This subject should now be put to rest. While searching several YouTube videos I ran across this one; YouTube - 2009 F-150 with "Detroit Locker"

It shows a video of a 2009 FX4 and demonstrating the "Detroit Locker" on a trailer with roller pins on one side. They attempt it on 4x4 only and just the two passenger side wheels spin. The Ford Rep explains this happens because when not locked it is an OPEN DIFFERENTIAL. They then activate the Locker and it climbs it perfectly.

SO there is the answer to my original post.....

 

I saw that video yesterday too... It does indeed lay thisa to rest. The Locker does not act as a LS when not engaged. However, once again the video is mislabeled... They call it a "Detroit Locker". This is another name brand... The locker in the FX4 is not made by Detroit Locker.

There is another test done by pickuptrucks.com that shows the f-150 on an incline with slippery surface, one tire getting traction, one slipping. they used a truck with a LS rather than the locker. The F-150 outperformed all other brands, but I wonder how the FX4 would have done with the open differential in 2WD.

 

So is that to say 4-wheel drive isn't really 4-wheel drive? That the rear can be locked in but the front continues to be controlled by the Advance-Trac system and will let those front wheels stop moving if slippage occurs?

 

Four wheel drive IS four wheel drive if all 4 wheels have traction. Open Differentials will transfer the most power to which ever wheel has the least traction. If both wheels have the same traction, they will both receive the same amount of power. The unfortunate part is that if one wheel looses alot of traction, or looses almost all of it, nearly all of the power will be transferred to that wheel.

A limited slip uses clutch discs physically connecting the two sides together. They allow just enough slip between the two sides so you can go around corners without squealing the tires, but grab together hard enough so if one wheel is on snow/ice with little traction, the other wheel with traction can still get power. However, limited slips can often be over powered if say one wheel is completely off the ground, and the other wheel is stuck good.

A locker can over come this, because they do not use clutch discs or anything like that. They pretty much lock all the gears in the differential together, allowing no slip, so it would have poor tire wear and bad street manners, but it guarantees both wheels will receive power no matter what.

It is actually possible to have both a limited slip and a locker in the same rear end like the Dodge Powerwagon, but it doesn't appear that Ford does this.

I'm not entirely sure, but I believe the advance-trac system is essentially a "fake" electronic type limited slip. Basically the computer will look the wheel speeds of a specific axle, and if it sees one wheel spinning significantly faster then the other, it will apply that wheels brake in hopes of transferring power to the other wheel. It is kind of crude, and doesn't really work all that well.

 

Good explanation Lead Head. But that combined with the above video raises another question:
Take an example where you have an uphill surface, the drivers side has no traction and you are in an FX4. I assume that from a stopped position, you will not be able to move up the hill in 4x2 of 4x4 unless you lock the differential (maybe with traction control you could but for this example assume you don’t have traction control). My question is this:
When you do lock the differential in 4x4 and begin to climb the hill, are you getting any help from the front axle, and if so from one or both wheels.
The question in my mind is if the front axel is an open differential (I assume the lockers are in the rear only) than there is only a 50 50 chance the front wheel receiving power is the one on a good surface. If it is the one on the slippery surface, that wheel cannot spin because in 4x4, the rear axle and the front axle are mechanically tied together. The locker keeps the rear wheels from spinning because one tire has traction and since the rear wheels can't spin, the front wheels can't spin.
I hope I explained my question clearly.