Sponsored

How to check if LSD is working properly?

Arrowhead

Well-Known Member
First Name
George
Joined
Aug 2, 2018
Threads
19
Messages
480
Reaction score
643
Location
Stillwater, NY
Vehicle(s)
2018 Wrangler JL Sport
Vehicle Showcase
1
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!
Sponsored

 

Bikemobile

Well-Known Member
First Name
Zak
Joined
Oct 17, 2019
Threads
2
Messages
253
Reaction score
260
Location
Gunnison, Colorado
Vehicle(s)
2018 JL
Vehicle Showcase
1
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

Well-Known Member
First Name
Brian
Joined
Jan 15, 2019
Threads
35
Messages
4,011
Reaction score
5,604
Location
Inland Empire
Website
www.instagram.com
Vehicle(s)
2018 JLU Sporticon, 1976 GMC K15 Lifted on 35's
Build Thread
Link
Occupation
Electrician/ Industrial Furnace MFG
Clubs
 
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.
 

jlroman2

Well-Known Member
First Name
Jorge
Joined
Jan 13, 2018
Threads
44
Messages
844
Reaction score
1,255
Location
Chicago, IL
Vehicle(s)
2018 Jeep Wrangler JLU Sahara (Granite)
Occupation
BCBA
Vehicle Showcase
1
Mine started making a clicking noise after adding bigger tires and lift :clap:
 

Sponsored

Lil Punk'n

Well-Known Member
First Name
Richard
Joined
Jan 13, 2019
Threads
5
Messages
173
Reaction score
277
Location
Talmoon Mn
Vehicle(s)
2018 wrangled jl sport
Occupation
Retired, School bus driver
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
 

Sponsored

Squibbles

Well-Known Member
Joined
Apr 20, 2019
Threads
14
Messages
300
Reaction score
245
Location
Albuquerque
Vehicle(s)
GTI, Ranger
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.
 

Bikemobile

Well-Known Member
First Name
Zak
Joined
Oct 17, 2019
Threads
2
Messages
253
Reaction score
260
Location
Gunnison, Colorado
Vehicle(s)
2018 JL
Vehicle Showcase
1
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

Well-Known Member
First Name
Chris
Joined
Nov 9, 2019
Threads
24
Messages
218
Reaction score
399
Location
Utah
Vehicle(s)
2020 Willys (2 door)
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

Well-Known Member
First Name
Zak
Joined
Oct 17, 2019
Threads
2
Messages
253
Reaction score
260
Location
Gunnison, Colorado
Vehicle(s)
2018 JL
Vehicle Showcase
1
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/
Sponsored

 
 



Top