Torsen vs Trac-Loc

[bruker]

Other than physical differences, what the difference between a Torsen Differential and a Trac-Loc Limited Slip? Is one better than another?

 

[gw33gp]

Torsen usually has a little higher torque bias and it should work considerably longer than a Trac-Loc without a rebuild. Trac-Loc will have less of a tendency to screech the tire when accelerating around a corner. When accelerating, the Torsen comes close to acting like a locker. Trac-Lok is less expensive.

 

[6.2]

That being said, I love my Torsen haha
It's great on and Offroad.

 

[pjtoledo]

2 very different differentials, with very different driving characteristics.

Trac Lok, has friction packs & springs to put a fixed amount of torque between the left and right rear wheels. In a straight line with similar traction to each wheel its great.
For the sake of explanation lets put the bias at 300 ft-lbs.

put one rear wheel on clean pavement, the other on slick ice. hit the gas and the ice wheel will start spinning (this is a really simplified explanation) and the wheel on pavement will only get the 300 ft lbs of torque. If the truck needs, lets say, 400 ft lbs to get it moving, 300 won't do it. The ice tire will spin faster, and the diff will get hot from the 300 ft lbs of friction.

In reality, 300 ft lbs should move the truck under most conditions, 'cept maybe going up a steep hill, front buried in mud, etc.

Now lets put all 4 wheels on ice.
the rear still has 300 ft lbs of bias between the wheels, so if you turn, the wheels won't have enough traction to over come it, and both will spin at the same speed. while turning that means one wheel is slipping and has lost traction.
that also means the rears being the same speed will try to push the front straight ahead. but hey, we're on ice and nothings perfect right?


the Torsen does not have clutch packs. it is a worm-gear differiential. it gets bias as the worm gears are forced sideways as power INCREASES. under low power there is no bias, it acts like an open diff, with one wheel hanging in the air it acts like an open diff, with one wheel on ice it acts better than an open diff.

while turning with one wheel on ice it won't try to push straight ahead, same on wet pavement, so steering is better under under low traction/power conditions as the bias does not kick in, or stays at a low level.
on dry pavement they are great, straight or turning, light load or heavy load.

some of the newer units, like Wave-trak (?) have different side ramps so the rate the bias comes on can be altered

I don't have any off road experiance with a Torsen, others will have to fill in that part.