How to check if LSD is working properly?

Arrowhead

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Well the one thing I found interesting is there is no preload spring between the clutch packs. That is normally what you would find and would keep the axles "locked" under light load, like having both wheels in the air. But with no preload spring, it might be normal to be able to rotate the wheels in opposite direction with no load.

If you want to test it old school, turn off the traction control, drive off the pavement with one wheel in dirt or grass and one still on pavement and floor it in 2H. If you leave a black strip on the pavement, it's working!



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Bikemobile

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The Auburn Pro Series LSD in my hotrod is very aggressive, and requires friction modifier additive to make is driveable on the street. So that one is always locked up and allows some slip when a mechanical difference in rotational speeds is introduced, like when turning. These can be a handful on wet or icy roads.

The trac lock allows a bit of wheel slip before the clutches heat up and lock the axles together with friction. This allows the diff to work like an open differential most of the time until it sees an unusual amount of wheel speed difference.

The one in my sport works seamlessly and very well. What I dont know is how much wheel spin is needed to lockup the clutches.

The eaton G80 in GM vehicles works similarly by using wheel speed differential to activate clutches and lock the axles together. These are clunky but pretty robust if not abused. They use a mechanical assembly that also unlocks automatically at a certain speed. 30 mph I think.
 

Maverick909

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I have it. Free spin the wheels no load they spin opposite from each other like an open diff. I know my LSD works great as I have had it come in handy quite a bit while wheeling. Just used it while doing broken arrow in the muck after it snowed.
 

jroman

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Mine started making a clicking noise after adding bigger tires and lift :clap:
 

Lil Punk'n

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My how times change. 50 years ago you could easily find someone who could tell you if LSD worked or not. Timothy Leary comes to mind. Now you ask a question like this and Jeeps pop into the conversation.
Nope I'm still thinking Leary. If you hallucinate the LSD is working
 

Lou Bunn

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Chong - take these man
Cheech - ok
Chong - hey man, don't take those
Cheech - I just took them!
Chong - oh oh oh wo wow man!
 

Squibbles

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How many miles on it? Trac-lok has never been known for longevity, it’s possible the clutch packs can wear out in as little as 30k.

If your still under warranty it’s covered to rebuild it.
I would hope they’d last 75-100k. I think it depends on how much you wheel and how big your tires are, I’ve noticed around 50k the one in my truck starting to slip a lot. What’s crazy is the limited slip in my Isuzu was still strong at 220k, I’m a big guy and had trouble making it slip. It was the OE GM diff which I discovered when replacing a pinion seal.
 

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I would hope they’d last 75-100k. I think it depends on how much you wheel and how big your tires are, I’ve noticed around 50k the one in my truck starting to slip a lot. What’s crazy is the limited slip in my Isuzu was still strong at 220k, I’m a big guy and had trouble making it slip. It was the OE GM diff which I discovered when replacing a pinion seal.
The GM ones can last a long time unless you drive around too much in 2wd and let er rip on ice snow dirt all the time.
 

basinite

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If you have a LSD and you have the rear end jacked up and the tires are spinning in the opposite direction you have something wrong. The tires should be be spinning in the same direction. As others have said, Jeeps have a clutch based system and there is a spring that puts tension on the plates, which is why the tires spin in the same direction when you have the rear end lifted.

I once blew out my clutch plates doing donuts in the snow and before getting it fixed I jacked up the rear end out of curiosity and the tires spun in an opposite direction like an open differential (before this they spun in the same direction). The guy that fixed my rear end showed me pieces of the clutch plates that had deteriorated. Luckily there was a magnet on the bottom of the differential that collected most of the pieces, so no damage was done to the gears.

I know it sucks to hear this, but if your tires are spinning in opposite directions, you have something wrong and the LSD is NOT working. Your vehicle will drive fine, the only reason I found out I destroyed mine was due to me parking one tire on ice at work, while the other tire was on dry asphalt. I got stuck when leaving work, since only the tire on the ice was spinning. If it wouldn't have been for that, I probably would have driven around for months without knowing my LSD was shot.

To the opening post, I highly recommend you take your Jeep to the dealer and have them open up the differential and see whats going on. Sounds like either they ripped you off and your Jeep didn't come with a LSD as advertised, or the clutch plates are damaged and need replaced.
 

Bikemobile

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If you have a LSD and you have the rear end jacked up and the tires are spinning in the opposite direction you have something wrong. The tires should be be spinning in the same direction. As others have said, Jeeps have a clutch based system and there is a spring that puts tension on the plates, which is why the tires spin in the same direction when you have the rear end lifted.

I once blew out my clutch plates doing donuts in the snow and before getting it fixed I jacked up the rear end out of curiosity and the tires spun in an opposite direction like an open differential (before this they spun in the same direction). The guy that fixed my rear end showed me pieces of the clutch plates that had deteriorated. Luckily there was a magnet on the bottom of the differential that collected most of the pieces, so no damage was done to the gears.

I know it sucks to hear this, but if your tires are spinning in opposite directions, you have something wrong and the LSD is NOT working. Your vehicle will drive fine, the only reason I found out I destroyed mine was due to me parking one tire on ice at work, while the other tire was on dry asphalt. I got stuck when leaving work, since only the tire on the ice was spinning. If it wouldn't have been for that, I probably would have driven around for months without knowing my LSD was shot.

To the opening post, I highly recommend you take your Jeep to the dealer and have them open up the differential and see whats going on. Sounds like either they ripped you off and your Jeep didn't come with a LSD as advertised, or the clutch plates are damaged and need replaced.
FALSE

Factory Dana Trac Lok differentials do not have springs. Therefore the tires do turn opposite of eachother when off the ground.

7449FD86-8622-4757-9707-72486E902B0C.jpeg


https://www.cjponyparts.com/omix-ad...gler-tj-cherokee-xj-for-dana-35/p/OMX1650906/
 

                           
























































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