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13 Posts
Discussion Starter #1
READ ALL THE WAY THROUGH BEFORE ATTEMPTING THIS. THIS JOB REQUIRES SPECIFIC TOOLS AND MAY BE OUTSIDE MANY DIYer's COMFORT ZONE!! The rear axle is a very finicky part of the truck and requires a very precise set-up.

First off, I'm using an axle housing that is not yet in my truck, and I've already gone through this process and am now backtracking to write this, so all my parts will look clean and new. Just forgive this fact and pretend its a mess like yours will be! :p

The tool list: (besides the obvious sockets, wrenches, etc.)

> Dial indicator with magnetic base/stand
> Carrier threaded adjuster adjusting tool
For this, you have some options. You can buy the specific tool made for this job. Just do a google search for "Chrysler 9.25 Spanner tool" or "Chrysler 9.25 threaded adjuster tool." Another option (this is what I used) is to use a dodge dakota (or similar) torsion bar. The hex head on the end of the torsion bar is the right size! (you'll see what I'm talking about later in this thread). Another option is to use a bolt with the right size head. Put a washer on the bolt to use as a stop and a nut behind that, and then use a socket, wrench, and very long extension on the nut!​
> Inch-Pound AND Foot-Pound torque wrench
> Clutch pack compressing tool
Again, you have some options here. You can do a google search and find the proper tool made for this job, or what I did was go to the hardware store and bought 2 coarse threaded 3/4" by 4.5" bolts, matching nuts, and 4 3/4" ID, 2" OD washers.​

13 Posts
Discussion Starter #2
Step 1) Jack up the rear of the truck, put the axle on jack stands, and remove the rear wheels. Get a oil drain pan and remove the differential cover.

Step 2) Remove the axle shafts. To do this, remove this bolt and pull the center pin out.

(The axle I'm using for this write up was only partially assembled... your carrier will still be in the housing at this point, so forgive the pics)

With that pin out, push in on the axles and let the c-clips drop, then slide the axles out.

Step 3) Remove the carrier from the axle housing. To do this, remove the carrier bearing retainers, and slide the adjuster tool down the axle shaft to back off the threaded adjusters. A torsion bar works great for the tool if you have one or can get it cheaper than the official tool (~$60). It would be smart at this step to count the number of turns each one gets backed off (for example, turn them out 3 turns, or make it an easy to remember integer... don't do say 2 and a partial turn) so when you reinstall it, you can put the adjusters very close to where they came out!!!

Here is the adjuster (your carrier will still be in place though, so it won't look like this).

This is the torsion bar's fit in the adjuster:

A wider picture of that:

This is what you'll be looking at down the axle tube:

So you should now have this:

Step 4) Remove the spider gear thrust washers. This was the biggest PITA until I figured out a method. The reason is, unlike an open differential that freely turns inside, the LSD does not!

To get the thrust washers out, you'll need to compress the clutches. I used 2 very large bolts, 2 matching nuts, and 4 washers. Dodge makes a special tool to do this, but going to the hardware store and getting bolts is much much cheaper! (these bolts are in the above picture).

The bolts have to go in 1 specific way to both fit, so start by taking one bolt, and pushing it through the ring gear side. When it gets to the middle of the carrier, slide the washer on it and finish pushing it through to the other side, and slide on the other washer and thread on the nut.

Push the other bolt through the same way, but put the washer on it from the start. Slide the other washer and nut on when it's through.

Tighten both down until the spider gears are loose (until you can wiggle them).

These are the thrust washers:

Take a small flathead screwdriver and push the thrust washers out.

With the thrust washers out, remove the clutch compressing bolts.

Step 5) Now, with the thrust washers out, remove the spider gears. To do this, put the carrier back in the housing, and tighten the bearing caps hand tight. Use the center pin to bind up the carrier by placing it part way in the carrier and letting it hit the axle housing. Place it far enough in to be secure, but not far enough to block the spider gears from sliding out.

Next, slide one of the axle shafts in the carrier, and use something for leverage. I used a crowbar inbetween the lugs, or you can use the wheel. It doesnt matter which direction you turn it, but turn it while using the center pin to hold the carrier still. This will force the internals to spin and the spiders will spin out.

Trust me, this is going to be A LOT easier with the worn out clutches than it will be when you put the spiders back in with the new clutches!!!

Step 6) With the spider gears out, pull the axle shafts back out and remove the side gears/clutches. The side gears should come free without a struggle, the clutch's pins are a tight fit in the carrier, so they require some extra motivation.

These are the side gears/clutches:

(Pay attention to how the belleville spring is oriented! Concaved away from the side gear.)

Step 7) Put the new clutch pack together exactly as the old ones are assembled... alternating splined clutch and tabbed clutch with the belleville spring against the side gear concaved away from the gear (the inner diameter up against the gear, the outer diameter up against the next clutch in the pack).

Keep reading for reassembly instructions.

13 Posts
Discussion Starter #3
Well that was the easy part! Now it's time for reassembly. Now you can see what a brand new set of clutches feels like while trying to put the internals back in the carrier!

Step 1) Install the side gears and clutch packs in the carrier. Again, make sure the belleville springs are against the side gear concaved outward.

Step 2) Now, the most fun part of the whole project!! Reinstall the spider gears into the carrier. An extra pair of hands will help you out a lot here, but I did it myself so it is possible. You need to place the spider gears on the side gears. VERY IMPORTANT!!! MAKE SURE THEY ARE EXACTLY OPPOSITE OF EACH OTHER!!! A good way to be sure is slide the pin through both. Obviously, you will have to hold the bottom one in place so it won't fall (this is where an extra hand will come in handy).

So once you are sure they are lined up, again use the pin as a stop and start turning the carrier using leverage on the axle, just like it came out.

So once you get them started into the carrier to where the carrier will hold them, you can let go:

Now you can use both hands to turn the axle and stop when the pin fits through everything.

Step 3) Installing the thrust washers.

Take the carrier with the newly installed spider gears back out of the housing.

Put the bolts back in the same way as described before to compress the clutches. Tighten them until the spider gears are loose (don't tighten them any more than needed, these are brand new clutches and don't need to be stressed).

With the bolts in, clean the thrust washers thoroughly and put some kind of grease or oil on them. You don't want any dirt on these! Slide the first one in place and hold it in with the pin.

Slide the other side in. I cheated here and used a pin from another differential to hold it in place. Since most people don't keep spare differentials lying around, just do what you can to keep the washer from moving, cause once you release the bolts, the parts cannot be moved!!

And with the bolts out, put the center pin in and tighten the lock bolt. Of course it will have to come out again once the axles go back in, but there are several more steps before then so I went ahead and put it back in place.

(BTW, this is where I was at when I started this. :p Now I have officially gone from making negative progress back to making zero progress!)

Keep reading for setting the backlash on the ring gear and preload on the carrier bearings.

13 Posts
Discussion Starter #4 (Edited)
Alright, time to place the carrier! This is part of what scares most people away from axle work, but since the same gear set is being used, and nothing was done to the pinion, there isn't much to it! As long as the backlash is set correctly, the contact pattern will not change and therefore does not need to be checked. But if you want peace of mind, you can check it with gear marking compound when everything is back together and the preload and backlash are both set.

(This picture was taken from the '01 Dakota FSM)

So there are a few things to keep in mind. First, these axles do not use shims for placement, as you have already discovered, they use threaded adjusters. These adjusters push against the bearing sleeve. The jobs of the adjuster are to 1) set the bearing preload to eliminate carrier play and 2) "place" the carrier right and left for setting backlash. Keep in mind... the bearing preload can be fine, but the backlash off, and the backlash can be fine but the bearing preload can be off, so it is a process that could potentially take several tries to get right. In fact, it could easily take a couple hours if you've never done one before, so if you don't have the time or patients, don't even start, cause this is not something to take lightly!!

Step 1) Start by removing the carrier and looking at the adjusters. Make them flush with the carrier housing... this will give you an even starting point for each side.

Step 2) Put the carrier back in and tighten the bearing retainer bolts hand tight using a socket. Turn the pinion gear fast and harshly by hand back and forth several time by half a revolution or so to ensure the ring and pinion are properly meshed and the carrier bearings are fully seated. Retighten the bearing retainer bolts if they are now loose. (You will have to put the transmission and/or transfer case in N to do this, or simply remove the driveshaft from the pinion yoke).

Step 3) Take the adjuster tool (torsion bar in my case), and thread in the adjusters in increments making sure you do both sides evenly! Do this until the carrier is "hand tight" (until you cannot wiggle the carrier right and left). You should lower the increments on each side as you progress to avoid going too far with one side. Now once again, quickly and harshly turn the pinion by hand back and forth like before to seat the bearings (you must do this every time you turn the adjusters, no matter how far they get turned!). Repeat this until everything is good and tight. You should now have a good starting point for an initial measurement.

You can save yourself some trouble by counting the number of turns you back the carrier off when you FIRST take it out while starting this project and when you put the carrier back in, turn them in the exact same amount. For example, turn each one out 3 turns to release the carrier, and then turn them back in 3 turns during this process. This will give you an even better starting point!

Step 4) Take an initial backlash measurement. To do this, set up your dial indicator as pictured.

(This picture was taken from the '01 Dakota FSM)

Make sure everything is at least hand tight and there is no play (except for the obvious backlash). With either side of the ring gear's teeth in contact with the pinion gear's teeth, zero the dial indicator. Now rock the ring gear so the other side of the ring gear's teeth are in contact with the pinion gear's teeth and read out how far the dial indicator moved. The inital target is between .003 to .004 inches.

Step 5) Now consider the measurement taken in step 4.

Case 1: If the backlash is on the high side of the inital target (greater than .004"), the carrier needs to be moved closer to the pinion gear.

If this is your case, back off the right (passenger side) adjuster first and then thread in the left (drivers side) adjuster by the same amount, ensuring that the carrier again has no play when you are done. Do this in a very small increment (ever so slight of a turn... keeping in mind that the backlash is in thousandths of an inch!). Once you've done this, rock the pinion back and forth like before to make sure the bearings are seated properly.

Case 2: If the backlash is on the low side of the initial target (below .003"), the carrier needs to be moved away from the pinion gear.

If this is your case, back off the left (drivers side) adjuster first, and then thread in the right (passenger side) by the same amount. Do this in a very small increment (ever so slight of a turn... keeping in mind that the backlash is in thousandths of an inch!). Once you've done this, rock the pinion back and forth like before to make sure the bearings are seated properly.

Now repeat steps 4 and 5 until you have a backlash measurement between .003" and .004".
Don't get confused, cause factory specifications state to set it between .005" and .008" The idea behind this is initially low setting is the preload still needs to be adjusted, so the adjusters still need to be moved, so moving just the right adjuster in to set the preload will psuh the backlash out.

Step 6) Consider the current backlash measurement. Factory spec is between .005" and .008". Since we are lower than factory spec, the right adjuster needs to be adjusted. This final adjustment is why up until now, everything was to be only hand tightened. For this final adjustment, use a torque wrench on your adjustment tool, thread in the right side adjuster until it reaches 75 ft lbs. Now reseat the bearings by turning the pinion like before. Now repeat this again turning the right side adjuster until you get 75 ft lbs and reseat the bearings. Repeat this until the right side adjuster is at a constant 75 ft lbs (no longer needs to turn to have 75 ft lbs of force on it).

Step 7) Now take another measurement. If backlash has not yet reached the the specified range, keep tightening the right adjuster until it is. But at this point, each time you turn the right adjuster, loosen the left adjuster by the same amount to keep the preload correct. Remember, each time you turn the adjusters, reseat the bearings before taking a measurement.

Just a hint, when you tighten the carrier bearing retainers, it will push the carrier slightly toward to the pinion, decreasing the backlash, so when you are setting the final backlash in step 7, go to the high side, like .008" or .009"

Step 8) Now with the backlash in range, use the torque wrench to make sure BOTH adjusters are still at 75 ft lbs. If everything was adjusted precisely, both sides should be close to even and little to no adjusting should be required to reach 75 ft lbs. If the adjusters are considerably off, just start over!

When you get the preload set on the bearings, turn the carrier to "feel" how easy it turns, and feel for binding (there shouldn't be any!) Its a good idea before you start to turn the carrier to get a feel for how free it should be.

Step 9) Now tighten the carrier bearing retainer bolts to 100 ft*lbs, and with everything now tight, take one last measurement to ensure the backlash is still between .005" and .008".

If everything is good, put that sucker back together and BE SURE TO INCLUDE 5oz OF FRICTION MODIFIER IN THE 80W-90 GEAR OIL!!! If you choose to use Fully Synthetic still include the Friction Modifier. These Fully Synthetic lubricates are 75W-90 but STILL INCLUDE Friction Modifier even when using Limited Slip rated gear oil.

13 Posts
Discussion Starter #5
Now that you have done this work, I would suggest you do a test drive with the radio off and listen for any odd noises coming from the axle. Specifically... pay attention to any driveline slap and listen for gear and bearing whine. There shouldn't be any issues if you followed the directions to a T, but its always good to check!
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