Retrofitting Torsen diff

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JuggNuttz

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Roger that. Thanks Tank.

Any idea how it would play with an ABS system not designed for it?

from my understanding (and im sure ill be corrected by someone) the Torsen is all mechanical, no electronics, so it should be a simple drop in upgrade.
 

BigJ

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Yeah gotcha. I was more wondering about how the systems will interact; we have wheel speed sensors that are monitored by the ABS system. What's going to happen when, for example you're in 4wh in snow on the highway and you hit some ice and that Torsen locks for a second? Will the ABS detect wheel speeds it doesn't expect as a result? Will it try and compensate? Will the Torsen fight harder, causing the ABS to fight even harder still? And on and on, etc...
 
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KaiserM715

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ABS activates when it sees a wheel(s) that are moving at a slower rpm than the other wheels. Then Torsen locks up when torque is applied through the driveshaft. When you are braking, the Torsen does not have any input torque applied, so it will not be locked (if I am understanding it correctly), thus having no effect on ABS.

The only electronic system that plays into the Torsen would be stability control and even then it would only be to further optimize Torsen operation.

Randy's Ring & Pinion has an excellent book Differentials: Identification, Restoration & Repair that covers gear type limited slips.
 

BigJ

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ABS activates when it sees a wheel(s) that are moving at a slower rpm than the other wheels. Then Torsen locks up when torque is applied through the driveshaft. When you are braking, the Torsen does not have any input torque applied, so it will not be locked (if I am understanding it correctly), thus having no effect on ABS.

The only electronic system that plays into the Torsen would be stability control and even then it would only be to further optimize Torsen operation.

Randy's Ring & Pinion has an excellent book Differentials: Identification, Restoration & Repair that covers gear type limited slips.

I'm definitely demoing my lack of knowledge here, but...

You're not braking, right? You've got your foot on the gas applying torque. But at the same time the ABS starts to try and do its job modulating the brakes. So you have toque at the Torsrn AND braking via the ABS... what then? Anything?
 

DubbsFaris

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Are you talking about the ABS or the TCS? I would think the ABS monitors only when the brake is being applied. Otherwise, wouldnt you be experiencing weird characteristics when 4 wheeling if you are not in Off-Road mode?
 

BigJ

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Ohhell. Duh.

Dub thanks for the smack upside the ole head there. Yep, I mean TCS and how it can pull throttle or modulate the brakes etc. Kaiser, sorry for the confusion.
 

KaiserM715

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I think J is referring to TCS or ESC (is that right?). In this case, the computer is still looking at and comparing wheel speeds.

For TCS, the computer will just cut power (unless all 4 wheels are spinning at the same speed, as the computer doesn't have anything to compare to) regardless of Torsen installation. (Edit: you posted while I was typing) I was not aware that TCS would apply the brakes, only cut power. I will look into that.

I don't think it will be an issue for ESC, either, but I will do some further research for backup and make another post.
 

pirate air

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Has anyone looked further into this ever since the '12s hit the lots?

Looked a couple weeks ago in the parts catalog and still no part number for the front torsion diff. I'll keep checking evey so often.
 
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