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Ok, So I got stuck in the snow a couple of times and a lot of high rev free wheel spinning was involved. Then finally I got stuck yesterday and as I was revving around 2-3k I heard this thump breaking sound coming from the rear. (Metal breaking sound followed by a Thump) and thats it. I noticed my drivers side wheel stopped spinning. I looked under and nothing seemed to be loose or broken. But I think my LSD went since both wheels dont spin at the sametime/rate. Anymore. Can anyone give me some trouble shooting advice, I cant take it to the dealer since there is too much snow outside and I dont have my snow tires until tuesday. I have a lift and all the tools just need some direction on what to do. Going to change the fluids tommorow and see if I can find some metal shavings. Also ill try spinning the wheel(s) and see if hte other one rotates with it.

I drove the car around the block and it seem to drive fine, if I loose traction it seems to favor one side more then before. but maybe its just in my head.

I read on a mazda forum that a blown LSD is when no power gets to the wheels past a certain RPM but dont know how accurate that is.

Thanks
 

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i would guess try spinning the wheels to see which way they go.. and maybe take the diff apart and see if you see ne shavings or broken parts. or if u can find a clean area try doing a burnout to see if there is a mark on both sides.. but that would be the last resort just incase it is broken dont want to mess up nething else.
 

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Discussion Starter #3
I didnt get a chance to do anything but a burn out since the dealer was closed and I couldnt buy the washers to replace my fluid. But tires did leave tracks.
 

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You probably broke something in the clutch pack in the LSD. I would find this pretty hard to believe if you were just spinning on the snow. Unless somehow your traction control locked up one of the wheels and over stressed the unit......The clutches would normally just slip when trac applies the brake to the individual wheel.
 

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^^^ clutches eh? :suspiciou
 

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Sorry, I was thinking back to my old 70 Chevy drag car. I think the IS300 has a Torsion style LSD. In that case, it could be a problems with the gears (not ring and pinon gears) See the diffferences below:

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Clutch-type Limited Slip Differential
The clutch-type LSD is probably the most common version of the limited slip differential.


Image courtesy Eaton Automotive Group's Torque Control Products Division



This type of LSD has all of the same components as an open differential, but it adds a spring pack and a set of clutches. Some of these have a cone clutch that is just like the synchronizers in a manual transmission.

The spring pack pushes the side gears against the clutches, which are attached to the cage. Both side gears spin with the cage when both wheels are moving at the same speed, and the clutches aren't really needed -- the only time the clutches step in is when something happens to make one wheel spin faster than the other, as in a turn. The clutches fight this behavior, wanting both wheels to go the same speed. If one wheel wants to spin faster than the other, it must first overpower the clutch. The stiffness of the springs combined with the friction of the clutch determine how much torque it takes to overpower it.

Getting back to the situation in which one drive wheel is on the ice and the other one has good traction: With this limited slip differential, even though the wheel on the ice is not able to transmit much torque to the ground, the other wheel will still get the torque it needs to move. The torque supplied to the wheel not on the ice is equal to the amount of torque it takes to overpower the clutches. The result is that you can move forward, although still not with the full power of your car.
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Locking and Torsen®
The locking differential is useful for serious off-road vehicles. This type of differential has the same parts as an open differential, but adds an electric, pneumatic or hydraulic mechanism to lock the two output pinions together.


Image courtesy Eaton Automotive Group's Torque Control Products Division



This mechanism is usually activated manually by switch, and when activated, both wheels will spin at the same speed. If one wheel ends up off the ground, the other wheel won't know or care. Both wheels will continue to spin at the same speed as if nothing had changed.

The Torsen differential* is a purely mechanical device; it has no electronics, clutches or viscous fluids.

Hummer!
The HMMWV, or Hummer, uses Torsen® differentials on the front and rear axles. The owner's manual for the Hummer proposes a novel solution to the problem of one wheel coming off the ground: Apply the brakes. By applying the brakes, torque is applied to the wheel that is in the air, and then five times that torque can go to the wheel with good traction.

The Torsen (from Torque Sensing) works as an open differential when the amount of torque going to each wheel is equal. As soon as one wheel starts to lose traction, the difference in torque causes the gears in the Torsen differential to bind together. The design of the gears in the differential determines the torque bias ratio. For instance, if a particular Torsen differential is designed with a 5:1 bias ratio, it is capable of applying up to five times more torque to the wheel that has good traction.

These devices are often used in high-performance all-wheel-drive vehicles. Like the viscous coupling, they are often used to transfer power between the front and rear wheels. In this application, the Torsen is superior to the viscous coupling because it transfers torque to the stable wheels before the actual slipping occurs.

However, if one set of wheels loses traction completely, the Torsen differential will be unable to supply any torque to the other set of wheels. The bias ratio determines how much torque can be transferred, and five times zero is zero.

*TORSEN is a registered trademark of Zexel Torsen, Inc.
 
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