Outer Limits 4x4 Board

Hey guys just wondering who have torsen diffs in the rear of their rigs?
I was wondering how do u make them "lock up"?

I'm currently driving the latest Mitsu Triton and it comes with a hybrid Torsen Viscous diff. When i 1st got it the car was like giving a tight LSD chatter around corners and it was fun to drift the Trition in the wet.
After 1k km it now feels like a normal diff.

Anyway being itchy i tried to ramp up the car in 2wd to check out the articulation. Next thing i can't go up any more as 1 wheel kept spinning.

I tried to left foot brake and apply some throttle.. Still spinning.
I tried to pull the hand brake a few clicks ........... Still spinning.

Am i doing it wrong or it's just the way the diff is?

To my understanding those who drive HUMMERS offroad they are thought to perform "brake throttle modulation" aka left foot brake to make the torsen lock up..

How about the Detroit Tractec.... Aren't they essentially a torsen diff too?

So what say u guys? What's your opinion.
Don't tell me to install a locker as this is a daily truck not an offroad rig.

your LSD is almost non-existant
the handbrake and the foot brake should have done it


chock the front wheels,
jack up both rear wheels at the same time,
make sure the handbrake is released
turn 1 wheel,

if the LSD is working the other wheel should spin the same way

if it is buggered, it will spin the other way

chikoroll_ wrote:your LSD is almost non-existant
the handbrake and the foot brake should have done it


chock the front wheels,
jack up both rear wheels at the same time,
make sure the handbrake is released
turn 1 wheel,

if the LSD is working the other wheel should spin the same way

if it is buggered, it will spin the other way

I'm not sure Torsens do this (not the same as a clutch pack LSD) - but a few clicks on the handbrake should cause it to tighten.

Haven't done anything silly, like friction modifiers in the rear diff oil?

I don't think u can use friction modifier on the diff as it's a helical diff. It bias torque, doesn't need friction to make it bite like a clutch pack lsd.
I guess the viscous coupling in the diff is suppose to be speed sensitive which provides the lock up.

I wonder what's the bias ratio for the diffs on the Trition.

Anyway my experience with helical diffs don't seem to provide any locking.
I recently installed a Modena Torsen diff up front on my Nissan Pulsar GTi-R and it' does not seem to make any difference other than slightly better turn in.

Or u guys reckon i didn't pull the handbrake hard enough and apply sufficient torque to make the Triton's diff to lock up?

I'd be surprised if you have a torsen. It sounds like you hve a clutch pack LSD. The problems you are reporting are common to all the clutch pack LSD's I've come across.

Torsens work very well under left foot braking.

To my mind a torsen with clutch packs on each side of it would be pretty much permanently locked or act as a very tight LSD. There wouldn't be any chatter.

Steve.

If it has a viscous component that has broken down ( they do that if severely overheated ) then there will be a strong odor from the viscous pack.

The silicone fluid can be replaced assuming all the shear plates etc are cleaned but the characteristics of the silicone are VERY important. The silicone works as a non Newtonian fluid changing its viscosity when subject to shear. Changes in the plate geometry and silicone characteristics allow the viscous pack to be tuned for different application.

All in all not a simple rebuild.

Gwagensteve wrote:I'd be surprised if you have a torsen. It sounds like you hve a clutch pack LSD. The problems you are reporting are common to all the clutch pack LSD's I've come across.

Torsens work very well under left foot braking.

To my mind a torsen with clutch packs on each side of it would be pretty much permanently locked or act as a very tight LSD. There wouldn't be any chatter.

Steve.

It's very rare to come across the Type II Racing Torsen that has a build it clutch pack lsd to provide pre load locking for aftermarket use let alone OEM.

I'm quite familiar with the characteristics with a normal diff, helicals, clutch pack lsds, detroit locker and a spool. Just very surprised that the helical diff doesn't lock up when u left foot brake in my version of a simulated test by ramping up the car.

The "hybrid lsd" that comes on my 2008 Triton looks like it runs a Type II Torsen diff with a viscous coupling attached to the side of the diff. Well that's what it says on the brochure and on the diff housing there's a sticker that says "hybrid lsd".

My next concern is it because i wasn't giving enough throttle while left foot braking? Partially because i was scared of toasting the torque converter? Or u think it's ok with giving throttle? Like handbrake at max click and bring up the revs to 2k?
Care to share as i notice u've got plenty of experience with autoboxes while offroading.

Any tractech users here?