Thought this might be helpful for Trac-Lok people. (30 to 200 ft/lbs doesn't seem like much torque. Is this typical for other LSD's?)

A common problem of the Trac-Lok differential is a chattering noise when turning corners. Before removing the unit for repair, drain, flush and refill the axle with the specified lubricant. Add a container of Mopar Limited Slip Additive after repair service or during a lubricant change.

After changing the lubricant, drive the vehicle and make 10 to 12 slow, figure-eight turns. This maneuver will pump lubricant through the clutches. This will correct the condition in most instances. If the chatter persists, clutch damage could have occurred.

The differential can be tested without removing the differential case by measuring rotating torque. Make sure brakes are not dragging during this measurement.


1. Place blocks fore and aft of both front wheels.
2. Raise one rear wheel until it is completely off the ground.
3. Engine off, transmission in neutral, and parking brake off.
4. Remove wheel, and bolt torque check tool #6790, or equivalent tool, to studs.
5. Use torque wrench on torque check tool to rotate wheel and read rotating torque.
6. If rotating torque is less than 30 ft. lbs. or more than 200 ft. lbs. on either wheel, the unit must be replaced.

 

very cool, thanks for this...I don't have a trac lock myself, but this is great advice for those that do

 

Excellent!

Thx


Quick question... I am curious, is the tracLok that comes in all new JK's the same TracLok that jeep has been using for years (decades) or is this a newer design?

I only ask as I have had great service out of my own 2008 JKU Sahara 3:73 with TracLok in the rear. The jeep jk with trac-Lok has been really capable off road. It was very surprising to have kept up with the jk rubicons we were trail riding with. Off camber inclines and some pretty crazy stuff at moon rocks and funny rocks (in Washington). The old-timers I wheel with (ages 50-75) were in agreement that "oh hell, these new jeeps are so dang capable, you really don't even need a locker. Just keep what you have. It's certainly anything better than what we've been using since the 70's."

I too have been really impressed with the combo BLD and TracLok. Granted, It's certainly not a locker and having to get the RPMs up to get the TracLok to engage the clutches can be a bit unnerving. It seems as if the clutch disks really "lock up" from 2800 to 3800 RPMs. Whereas the rubicons with their 4:1 and lockers can just barely moan, quietly & confidently chugging along at 700 to 1200 RPMs, happily crawling away. Whereas I had to loudly wind it up and not as gracefully make my approach.

Even the military J8 uses TracLok: http://www.jeepolog.com/UserFiles/en...oad%20test.htm

I still went wherever the rubicons went, I just did it with a little more "flare."


Second Question: Lastly, I have 47000 miles on the odometer. I have been reading that I should expect to only get 75k to 100k on this rear?

Is that true? Then what? Do I just add Aussie lockers? Detroit true track? Selectable lockers from Yukon or ARB?

It is a bit disserning to feel like I am just on a ticking time bomb, waiting for my rear to grenade (or clutch wear out) in some fantastically inopportune time.

 

100 to 200 ft/lbs is a typical breakaway torque for a clutch plate style of LSD. The clutches normally have preload springs to set the static torque. As power is applied from the driveshaft the bevel on the spider gears will apply even more clamping force to the clutches. The clutches will wear out over time. I don't know about a trac loc, but a Chevy positraction can be rebuilt.