Posi traction burnout

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jabroni619

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The rear diff isn't a posi-track diff, its an open diff with an e-locker. The e-locker from my understanding can only be engaged in 4wd
 

Loufish

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An open diff like ours in 2wd, will depending on the traction, can spin both tires if the conditions are right. Mine acts like a locked rear many times off road...but not always...
 

rtmozingo

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An open diff like ours in 2wd, will depending on the traction, can spin both tires if the conditions are right. Mine acts like a locked rear many times off road...but not always...

I've heard reports of this, and suspected it myself, but to see you say that makes me really think the computer might be doing some 'posi-trac' shenanigans even in 2H.

So, if this is true, does the computer cut power, apply brakes, or both?
 

zombiekiller

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I've heard reports of this, and suspected it myself, but to see you say that makes me really think the computer might be doing some 'posi-trac' shenanigans even in 2H.

So, if this is true, does the computer cut power, apply brakes, or both?

all of the above. I have a feeling that the lack of locker availability in 2wd has a lot to do with the stability control and traction control systems applying brake based on wheel speed and yaw.

Having the rear locked would probably cause catastrophic consequences if you arent driving super smoothly once the truck started trying to slow down one of the wheels with braking.

The braking system is super complicated by itself with all of the variable brake bias and booster pre-charge functions.
 

rtmozingo

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all of the above. I have a feeling that the lack of locker availability in 2wd has a lot to do with the stability control and traction control systems applying brake based on wheel speed and yaw.

Having the rear locked would probably cause catastrophic consequences if you arent driving super smoothly once the truck started trying to slow down one of the wheels with braking.

The braking system is super complicated by itself with all of the variable brake bias and booster pre-charge functions.

I agree. That said, that means higher rear brake wear, correct?
 

Edbert

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Sheesh guys, be nice to our new members!

It is news to me that these are truly "open" in 2WD, not based on my lack of reading but on the way it drives.

Mine feels like a soft-locker (like a tight clutch-based LSD) in slow speed turning. I can feel a slight shudder and hear some tire noise in very low-speed tight turning. Feels like a MUCH softer version of the "Detroit locker" in the 9-inch of my car, but the neighbors can hear that thing (loud clanking sounds) when it slips and there's none of that in the Raptor.

EDIT TO ADD:
That slipping I hear is most noticeable at under ~7mph on gravel.
 
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