Front differential failures

[airline tech]

Any chance of getting the code they had for the ABS system?

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[Colo_Ranger]

And what actually failed?

 

[fusseli]

4 Lo has a silly amount of torque that gets transferred. I have rarely used it in all my years of trucks and off road. Good for technical crawling, or serious stump pulling power. Otherwise it is not more traction than 4 Hi.

This. 4low is NOT for snow and ice, or braking to stop spinning wheels.

 

[Frenchy]

As much as I hate to say it, this sounds like an issue with the Nut holding the Steering Wheel.........

 

[harringtondav]

The only thing that would make sense as a possible here, The Transfer from 4-Hi to 4-Lo is not immediate and there is a delay. Must be in (Neutral) and stopped or speed less than 3 MPH, speed input comes from the (ABS) wheel speed sensor inputs.

My THEORY and this is just that a (THEORY)

You went to neutral, saw the flashing (transition) on the dial, put it back in gear, and began giving it gas - Still in 4-HI.
Now I know that (ALL 4) wheel speed sensors tie into getting it to shift into 4-LO.
So, the question is - and the (WHAT IF?) it takes any combination of them or does it require (ALL) to see (3 MPH) or less to allow the shift into 4-LO

So being in a (On Ice) situation, uneven traction from each tire, I think the system ALLOWED a shift into 4-LO and all wheels (mainly) the Fronts were not within the specs (3-MPH) or less.
So, the transition actually happened when all parameters were not met.

So, with you on a (Second) Differential, something else is wrong on the (Control) side of system and it's letting it get into 4-LO without the proper safeguards (inputs) to prevent damage.

If the Ranger is set up like the New Process X-fer case on my old Durango, 4L is a non-synchronized planetary shift in the X-fer case. Thus the low, rolling speed neutral shift. Neither differential changes anything or cares.
But the engine torque to the diffs is increased by a function of the low range reduction ratio, 2.7:1.
I'd think the higher torque load capacity is designed into the differentials, to the point of handling a full wheel lock up torque converter stall. ....1900 rpm was the healthy torque converter limit on the Durango. But if the attachment is correct showing 250+ ft-lb, the drive shafts/differentials see 675 ft-lb, more if the wheels were spinning at a higher engine rpm.
So maybe the sudden braking caused a torque spike which failed the front diff, which is normally smaller than the rear diff.
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