Torsen One Wheel In The Air

Does anyone know exactly how the front torsen differential reacts to having one wheel in the air? Do the electronic nannies take care of it and apply load to engage the diff or do you have to use left foot braking. I've not had the situation come up myself but I've been in areas where it was a possibility and it got me thinking. I read somewhere that the TBR is 2.5 and there is no pre load. My other option is to jack up 3 wheels and test it out but thought someone on here might know.

That is a really great question, one I have been thinking about...

The Torsen works AWESOME with some type of traction control that locks up the spinning (off the ground) wheel...I had one (Torsen) in the rear of my 04' Titan 2wd and the factory limited slip was all electrical using the ABS because no type of locker/LSD was offered in the rear.

So yeah I'd love to find if Ford took advantage of the nannies to use to get the most out of our front LSD.
BTW Only done limited crawling and the front never really slipped a wheel so far...guys doing Moab would most likely know...

Torsens lock the axle together. You won't have a problem.

ReefBlue said:

Torsens lock the axle together. You won't have a problem.

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That's not true when one wheel is in the air...I.E has no load on it:

From the Torsen website:

"You probably see by now that in extreme situations, such as when a tire is lifted off the ground completely, that zero X TBR is still = zero. So, yes, in that case, the Torsen is limited. But that is why the product is classified as a limited slip differential. However, keep in mind that I said that the Torsen requires some reaction load on both sides to work against."


Your graphic is pretty and explains the Torsen LSD concept but does nothing to explain how the truck handles a situation where one wheel is in the air...thus providing no torque to be transferred. Left foot braking might work but I was hoping someone who knew how it's incorporated into the raptor with all it's nannies.

Here's a great link from Torsen https://torsen.com/ask-torsen-torque-bias-ratio-functional-questions/

pbtjrlmrt said:

Left foot braking might work but I was hoping someone who knew how it's incorporated into the raptor with all it's nannies.

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You would think with all the tech built into the Raptor that adding traction control to the front axle to work with the Torsen would overcome the only downside to the Torsen...and it would be even funnier if that is built in and nobodies saying a word about it...

Great question to ask the instructors at the Raptor Assault....

Surprised no real answers on this one....

So has anybody had an opportunity to test this out? Do we know what happens yet?

My experience was when I was high centered in snow and it seems like I wasn’t getting both wheels to go at the same time… I would’ve thought that there was at least enough load on both wheels that the differential would lock them up.

I had no load on left front tire and i sat spinning / almost trying lurching backward in 4 low...but going no where then applied brake and it grabbed got me out so that's as close as ive got. Hard to explain.

moonjim said:

I had no load on left front tire and i sat spinning / almost trying lurching backward in 4 low...but going no where then applied brake and it grabbed got me out so that's as close as ive got. Hard to explain.

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That's clear. It sounds like Ford missed a bet on single-wheel braking to make the Torsen work properly.

Trail control uses its own algorithms to apply ABS individually and independently to each wheel, doesn’t it? Will it lock up a spinning wheel and handle the situation better if it is engaged?