GEN 2 Should order the front axle with TORSEN® Differential $500

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Ecoop

Full Access Member
Joined
Feb 7, 2017
Posts
158
Reaction score
86
Location
California
Yes, it seems like every time I go on a run something breaks. I was going on a Baja run this month but I had to cancel because I don't trust it.
 

EricM

FRF Addict
Joined
May 11, 2016
Posts
3,492
Reaction score
3,228
Location
OHIO
Well, I just scattered my front Torsen diff today at the sand dunes in pismo, ca. Pretty loud went it all comes apart...and violent.


We blew up an 8.8 Ford SRA with a Auburn Pro diff just ******** around in the snow with a 200 HP 2.3L turbo 4-cyl in a 3500 lb car. Doesn't take all that much to break shit sometimes.
 

Loufish

FRF Addict
Joined
Dec 30, 2017
Posts
1,050
Reaction score
642
Location
Burbank CA
Wow..did this get off track...I believe the original question was if ordering a truck without the 802 package, is it worth it to order the front Torsion diff as a stand alone option for about $500...
From a cost analysis, it's a no brainer as installing it later would cost 3-4 times that...
From a "do I need it" stand point, there is no real right or wrong answer...If your Raptors life will be spent mall crawling, then you won't miss the Torsion diff...If you plan on off roading needing 4wd, or simply wet, snowy, or slippery conditions needing 4A then I would say "yes" order it...and of course any type of rock crawling it turns back into a no brainer...

I've been reading all these posts and one thing has stuck me...why people are running in 4A in hard dry hi traction conditions?...I did run mine in 4A by accident (ok, I screwed up...) for a short while and did feel the steering get heavy (which is why I checked to see if I was in 4A) but not so crazy as to wish I didn't have it for looser conditions..AND when I have run 4A on dirt roads and such the torque steer was basically un-detectible.

And finally...the Torsion unit is a LSD type (although "slip" isn't correct) differential because it allows the inside and outside wheels to turn at different speeds while still under low to medium power.
 

rtmozingo

FRF Addict
Joined
Aug 3, 2017
Posts
1,142
Reaction score
748
Location
North Texas
Wow..did this get off track...I believe the original question was if ordering a truck without the 802 package, is it worth it to order the front Torsion diff as a stand alone option for about $500...
From a cost analysis, it's a no brainer as installing it later would cost 3-4 times that...
From a "do I need it" stand point, there is no real right or wrong answer...If your Raptors life will be spent mall crawling, then you won't miss the Torsion diff...If you plan on off roading needing 4wd, or simply wet, snowy, or slippery conditions needing 4A then I would say "yes" order it...and of course any type of rock crawling it turns back into a no brainer...

I've been reading all these posts and one thing has stuck me...why people are running in 4A in hard dry hi traction conditions?...I did run mine in 4A by accident (ok, I screwed up...) for a short while and did feel the steering get heavy (which is why I checked to see if I was in 4A) but not so crazy as to wish I didn't have it for looser conditions..AND when I have run 4A on dirt roads and such the torque steer was basically un-detectible.

And finally...the Torsion unit is a LSD type (although "slip" isn't correct) differential because it allows the inside and outside wheels to turn at different speeds while still under low to medium power.

Torsen is a no brainer, and it is an lsd. 4A is safe for all conditions, and necessary if you want to put all the power down in sport mode (or even normal mode)
 

Ecoop

Full Access Member
Joined
Feb 7, 2017
Posts
158
Reaction score
86
Location
California
what mods are you running, if any? Sorry to hear about your troubles.

Standard stuff: tune, intercooler, downpipes, thermo, air intake. I was backing out of camp in 4h went i first heard/felt it pop and then on a bowl and bang locked up grinding popping all kinds of bad sounding crap. Drove back in 2wd and called it a day.
 

FireStarter

Member
Joined
Jan 2, 2019
Posts
1
Reaction score
3
Location
SoCal
I’d like to think that the WRX STi is a high performance awd car. A helical front diff will make the biggest difference at slow sharp turns under load. Also, the civic type r uses a helical front differential, and it is an extremely well balanced vehicle.

Since it’s North American debut it has only had a helical front differential (same principle as torsen). In 2006 and on the electromagnetically energized clutch pack center differential (dccd) switches from an open differential to torsen while still retaining the em clutch pack. In 2007 and on the rear clutch pack limited slip differential was swapped out for a torsen unit.

Helical differentials utilize the thrust generated from their gear profile. The thrust provides internal friction to provide a locking effect. The thrust is proportional to the amount of torque flowing through the differential.

If little torque flows through the differential then you’ll have little to no locking effect, which is why ice and lifting a wheel thwarts helical diffs.

Unless you’re loading up your driveline with a lot of torque while turning, the torsen differential will not lock up. If you do send a lot of torque through the diff and are simultaneously turning, then the locking effect will simultaneously attempt to slow down the axle spinning faster than the carrier, and speed up the one that is slower.

Driving aggressively with a front helical diff in awd isn’t problematic. I took long sweeping turns at over 140mph under full throttle and couldn’t notice it. The biggest difference is slow speed sharp turns like auto cross. And that induces under steer. Which I quickly learned to brake a little earlier, rotate, and get on the throttle harder.

I made this account because I saw this guy trying to pass off lies such as no awd car comes with one, or why doesn’t 99% of cars have em. Torsen brand diffs are much more expensive than an open diff. There is zero reason financially for a manufacturer to add extra cost unnecessarily.

Torsen differentials are performance differentials. They are only offered from the factory on performance oriented vehicles, or for center differentials like on the 200 series land cruiser.

Don’t listen to this troll. Feeling their torque biasing diff in their driveway... must be some aggressive driveway driving.



It seems you are unaware 4A is marketed as a 24/7/364 setting, intended to bring full-time AWD to the Raptor regardless of road surface or condition. And when paired with an open diff, it works exactly as advertised. It performs just like any other full-time AWD found in modern minivans, sedans, and SUVs.

But when paired with the Torsen diff, a device you won't find in any other full-time AWD setup, the limited slip action of the Torsen diff actively resists driver inputs. Nothing wrong with that, it is simply a tradeoff for having a mechanical LSD.

But for myself and many other FRF members, this steering feedback is annoying and makes 4A unsuitable for 24/7/365 use. As a result, I use 4A exactly like I would use 4H, reserved only for slippery surfaces.

The OP asked if he should get a Torsen, everyone said yes. All I was doing was pointing out the downside of the Torsen. And then everyone lost their shit because apparently the Raptor is flawless and criticizing any part of it is against forum rules.
 

1roadking

Full Access Member
Joined
Aug 7, 2018
Posts
293
Reaction score
218
I like the Torsten now that I’m getting use to it but torque steer is a real issue in 4A. When you hit it on a dirt road or snow the front pulls hard back and forth as it hunts for traction. It grabs and goes which is nice but it’s definitely something you have to get use to.
 

goblues38

FRF Addict
Joined
Oct 27, 2018
Posts
2,697
Reaction score
3,984
Location
STL
this thread was hard to follow.....

I have owned several Audi's in the past....ones with true Quattro, not the cheap haldex ones.

My raptor has the Torsen Diff, and no...it does not drive like my Audi's did. there is torque steer in certain conditions. But for me, in this big truck, that is a little helpful to me in providing feedback to the driver that traction is there.

I would have to spend real seat time in good and bad weather in a non torsen equipped truck to see what is better to me.

My truck is in 2h 98% of the time. It goes to 4A in heavy rain or light snow where sudden loss of traction could be bad. my truck is a garage and pavement princess. not sure it will ever see 4H....maybe if we get significant snow.
 
Top