JDub11

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Is it possible you still had your foot on the accelerator when you shifted into 4wd? If your rear tires were spinning and the front were not they would be traveling different speeds. When the shift occurred the wheels would have been forced to turn the same speed creating slip somewhere. This would also account for a hard shift and a clunk.





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WorkingMan

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Yes, based on the manual and my understanding is that 4WD (High) can be engaged at speeds up to 55MPH. 4WD Low however is MUCH different, you need to be in neutral when transitioning in and out and and be rolling/moving very slowly (<25 MPH) you need to take care not to shift too quickly while you're doing it.
I know what the manual says but I don't trust the idea of engaging the 4WD while going any faster than 15 - 25 MPH.
 

limeade

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I know what the manual says but I don't trust the idea of engaging the 4WD while going any faster than 15 - 25 MPH.
The transfer case has synchronizers in there which allows for 4Hi engagement at higher speeds. If for whatever reason (speed, RPM's, etc) the synchro's aren't lined up, you won't be able to complete the shift into 4Hi. As long as the synchro's are aligned, it'll go in without any damage, grinding, etc.

I've done it at speeds up to 70 mph. At 71 mph+, it won't shift into 4Hi. So I figure that's the speed where the synchro's are saying NOPE!
 

Ridgerunner542

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Exactly what I said, there's no mechanical failure that would cause wheel lock up from the transmission, transfer case, or even the locker that would be temporary. A chipped gear or busted Sprague could cause lock up, but it would be permanent damage. Locking the locker on the road may cause drifting (some of us do that on purpose), but it wouldn't cause wheel lock up as described. This was an abs failure all the way. For whatever reason the traction control applied the brakes to one wheel hard enough to cause a loss of control.
You guys are 100% correct. This is a software error. If it were a mechanical error the would be physical damage to components.

When he shifted on the fly it caused a bit of wheel spin when the front differential engaged, traction control threw a fit locked up the brakes and unfortunately threw the Jeep into a tail spin resulting in a rollover.
End of story.

I have a mild lift on my current vehicle and the off ramp exit for my work is 35mph, if I hit the rumble strips while going threw the curve over 45mph it engages the traction control and immediately wants to put the truck in a circle. The first time I thought I was going to put it into the guard rails it threw the ass end around so hard. It scared the shit out of me. Now I can replicate the same event every time but I must be going faster than 45mph.
 

Ridgerunner542

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The axles of the Willys and the Rubicon are not the same, The Rubi has an electronically activated locker, where as the Willys has a conventional Limited Slip, if equipped.
It has nothing to do with the differentials in the rear. It’s the traction control. One of the sensors or modules are bad. I don’t have the patience to read through 23 pages of banter to find out what they replaced.
 

roaniecowpony

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....

I have a mild lift on my current vehicle and the off ramp exit for my work is 35mph, if I hit the rumble strips while going threw the curve over 45mph it engages the traction control and immediately wants to put the truck in a circle. The first time I thought I was going to put it into the guard rails it threw the ass end around so hard. It scared the shit out of me. Now I can replicate the same event every time but I must be going faster than 45mph.
That sounds pretty exciting. Not the good kind. Do you think lifting it caused it to do this?
 

SirMagnus89

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It has nothing to do with the differentials in the rear. It’s the traction control. One of the sensors or modules are bad. I don’t have the patience to read through 23 pages of banter to find out what they replaced.
I get what happened here after the OP posted the trouble codes. If you looked at what i replied to you would understand my comment. Don't be a salty dog and look at the back story.....looks like you are also adding to said banter that you don't want to read through.
 

Ridgerunner542

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That sounds pretty exciting. Not the good kind. Do you think lifting it caused it to do this?
No, the lift wouldn’t change a thing. Upping the tire size from 31 to 33. Meh, 2 mph slower reading on the clock at that speed. Just fooled the traction control into thinking the vehicle is going into a skid. Road speed plus steering angle plus the vehicle drifting across the road when it does hit the rumble strips, maybe the harmonics have some play in the game too. The vehicle safety system is actually doing its job just really overreacting to an in control situation.
 

NBB

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Is it possible you still had your foot on the accelerator when you shifted into 4wd? If your rear tires were spinning and the front were not they would be traveling different speeds.
That’s what this all sounds like to me. When a wheel either slips or locks up, it’s well known most abs computers are going to have difficulty processing it. Sounds like both may have happened here. The codes he’s posting don’t indicate any particular sensor issue, just that out of range system values were being read - likely by different modules from different manufacturers - trans and brake. Seems the takeaway is to make sure to shift into 4wd on dry pavement, if you are moving at a faster speed. I say nobody finds anything wrong with the jeep - with the caveat of the usual mindless part swapping. Seems also a more perfect processing algorithm should prevent such a thing, but I’m sure the tradeoffs are complicated.
 

roaniecowpony

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No, the lift wouldn’t change a thing. Upping the tire size from 31 to 33. Meh, 2 mph slower reading on the clock at that speed. Just fooled the traction control into thinking the vehicle is going into a skid. Road speed plus steering angle plus the vehicle drifting across the road when it does hit the rumble strips, maybe the harmonics have some play in the game too. The vehicle safety system is actually doing its job just really overreacting to an in control situation.
You don't think the lift might allow more body roll and influence the system logic?
 

four low

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You guys are 100% correct. This is a software error. If it were a mechanical error the would be physical damage to components.

When he shifted on the fly it caused a bit of wheel spin when the front differential engaged, traction control threw a fit locked up the brakes and unfortunately threw the Jeep into a tail spin resulting in a rollover.
End of story.

I have a mild lift on my current vehicle and the off ramp exit for my work is 35mph, if I hit the rumble strips while going threw the curve over 45mph it engages the traction control and immediately wants to put the truck in a circle. The first time I thought I was going to put it into the guard rails it threw the ass end around so hard. It scared the shit out of me. Now I can replicate the same event every time but I must be going faster than 45mph.
So "Traction Control" is the culprit ; unintended consequences of a " for your Safety Mandate "
Can it be disabled without a Tazer ? I now disable it like the StartStop, a push of the buttons at each start cycle
 
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pablo_max3045

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So "Traction Control" is the culprit ; unintended consequences of a " for your Safety Mandate "
Can it be disabled without a Tazer ? I now disable it like the StartStop, a push of the buttons at each start cycle
I thought you can turn it off with a button, can't you?
All of our Rubicons over on this side of the world have the "auto 4x4" option, which you can finally get in the US on 2021 models. So, we don't really have to worry about the sudden change.
I had this happen on an old school Montero with shift on the go 4x4 as well, though I only did a couple 360's without the rolling.
Not sure if the wheels suddenly "bit" or what. As soon as it engaged on the snow covered road, it was like a tilt-a-whirl. I was under compression braking at the time though... so perhaps there is some relation.
 

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