My Dana 44 is singing to me

The rear 44 on my 96 ZJ is making a humming noise:wow: I thought at first it was bad brakes but after replaceing them i came to relize its coming from the diff. The jeep came from the factory stock with it. Any ideas what could cause this befor i crack open the diff cover....
 
Its a crap aluminim 44.. thats the problem...
 
It has a junk D44 with an aluminum center section. Don't waste you're time fixing it, replace it wIth a real axle that has a steel center secton(and not a D35....).

A 8.8 from a Ford or a XJ D44 are some choices, but will need all the brackets welded on. If you have ABS that is also a concern.
 
If it is your carrier bearings, you'll have to pull the carrier, then remove the bearings without damaging the shims (you need a bearing splitter with a press or a special bearing removal tool to remove the bearings cause they're pressed on) and put the new bearings back on. If you damage the shims while pulling the bearings, which isn't hard to do, then you'll need a dial caliper and some new shims to put the same exact shims back on. You'll also need a press to put the new bearing on each end, then put the carrier back in, torque the bearing caps to spec and you're good.

If it's a pinion bearing you'll need an impact wrench to pull the pinion nut, and a bearing splitter and press to get the bearing on and off. Make sure to check the bearing preload with an in-lbs torque wrench when you're done although it should be the same as long as you put all the shims back exactly and torque the pinion nut back on right. I'm assuming your axle uses shims like most Dana axles. If it uses a crush sleeve then it's a bit different.

If this sounds like too much, then it's time to just take it in and have everything done by a pro, or put a different axle in. If you've wanted to throw a locker in there, now would be a good time since you'll be tearing into it anyways.
 
The center section is very weak. If you jack it up under the center section it will bend the axle housing most of the time. It is not worth fixing...
 
get a rebuild kit and barow a few tools like a bearing splitter and go to town, it really isnt very hard to change the bearings as long as you have half a brain and do it one at a time. I would also sugest cleaning out the housing while its apart and getting some one to look at the gears to make sure they are wearing ok, since your in there anyways
 
Don't waste your money on the aluminum D44, the reason the bearings fail is because the center section is junk. It spreads under load and the core shifts which wipes out the bearings. Rebuilding it won't fix the cause of the failure.

You would be better off with a D35 with a truss added and some alloy shafts or a super 35 kit. If you don't want to weld brackets on this is a much better choice.

In this case a D35 is a better axle then the aluminum D44 is...
 
Johnnybegood_5 said:
Well do, unless some one can get me a link that will show me how to measure the angles and what not for swapping in a new axle. This is my DD so anything that could cause a death wobble is very bad:shocked:

you have an axle in there right now...

the angles are right on the axle that is in there...

if you cant figure out how to measure the angles of the spring and link mounts off the old axle, how can you expect to place new ones?
 
Wow, lots of we'll say "questionable" tech in this thread.

So lets start at the basics. What the main cause of failure of the Aluminum D44 is the carrier bearing pre-load. Dana corp decided the best way to assemble this axle was to build the center section and then press in the axle tubes. Not good for maintaining the proper carrier bearing pre-load. Now whith the excessive carrier bearing pre-load we now start to have bearing problems, mostly pitting. When the pitting gets too extreme, it now statrts forcing the carrier bearing races to spin in the housing. Due to the aluminum material of the bearing caps and center section the spinning races remove enough material so that no matter what you do the races will never be properly retained even if you replace them. Now just replacing the bearings will not solve you problem either without correcting the excessive pre-load on the carrier bearing, if you housing isn't screwed.

So now to how to fix your problem? Well since the rear of a WJ has a triangulated upper link set-up finding a donor axle isn't all that easy without some sort of fabrication. Check out the clayton off-road website for a rear axle bracket kit, but like Opie said if you can't figure out how to measure the existing angles, then you probably don't want to do this on your own.

Swapping in a Dana 35 out of a similar equipped WJ is a decent option, but one that will be expensive as well if you want to upgarde it. Don't forget to put in a longer rear driveshaft if you opt for the Dana 35.

Now this information is coming from someone who knows a thing or two about these rear axles, so your mileage may vary.

Good luck with this.

BC
 
i knew the bearing issue was caused by assembly but I dodnt know why, thanks for sharing. I still say try and rebuild the one you have if you open it up and find worst case senario the bearing races are fubar then your out what maybe 2 hours time? and if they arent your 1/3 the way done and should be able to get the bearings same day
 
Bryan C. said:
Wow, lots of we'll say "questionable" tech in this thread.

So lets start at the basics. What the main cause of failure of the Aluminum D44 is the carrier bearing pre-load. Dana corp decided the best way to assemble this axle was to build the center section and then press in the axle tubes. Not good for maintaining the proper carrier bearing pre-load. Now whith the excessive carrier bearing pre-load we now start to have bearing problems, mostly pitting. When the pitting gets too extreme, it now statrts forcing the carrier bearing races to spin in the housing. Due to the aluminum material of the bearing caps and center section the spinning races remove enough material so that no matter what you do the races will never be properly retained even if you replace them. Now just replacing the bearings will not solve you problem either without correcting the excessive pre-load on the carrier bearing, if you housing isn't screwed.

So now to how to fix your problem? Well since the rear of a WJ has a triangulated upper link set-up finding a donor axle isn't all that easy without some sort of fabrication. Check out the clayton off-road website for a rear axle bracket kit, but like Opie said if you can't figure out how to measure the existing angles, then you probably don't want to do this on your own.

Swapping in a Dana 35 out of a similar equipped WJ is a decent option, but one that will be expensive as well if you want to upgarde it. Don't forget to put in a longer rear driveshaft if you opt for the Dana 35.

Now this information is coming from someone who knows a thing or two about these rear axles, so your mileage may vary.

Good luck with this.

BC


BTW he has a ZJ.

In my Chrysler training classes they stated besides the assembly issues, lifting the vehicle by the center section would cause the housing to distort which would also cause carrier bearing failure.
I was told that Dana didn't heat cycle the center section correctly and after it heat cycled from normal use it would suffer core shift. They did attempt to address this problem, but I'm not sure how well it has worked since I'm no longer a tech for mopar. I have seen the pinion shift so much it was on an angle to the ring gear making it impossible to get the correct gear pattern. Jeep started replacing assemblies and not allowing rebuilds because the housings were not in rebuildable condition most of the time.

So what is so "questionable" about this thread?

BTW what makes you so much more knowledgeable then everyone else?
 
TNT said:
BTW he has a ZJ.

In my Chrysler training classes they stated besides the assembly issues, lifting the vehicle by the center section would cause the housing to distort which would also cause carrier bearing failure.
I was told that Dana didn't heat cycle the center section correctly and after it heat cycled from normal use it would suffer core shift. They did attempt to address this problem, but I'm not sure how well it has worked since I'm no longer a tech for mopar. I have seen the pinion shift so much it was on an angle to the ring gear making it impossible to get the correct gear pattern. Jeep started replacing assemblies and not allowing rebuilds because the housings were not in rebuildable condition most of the time.

So what is so "questionable" about this thread?

BTW what makes you so much more knowledgeable then everyone else?

Hmm ZJ it is. For an easy swap, a TJ rear D44 will work but I am told that the upper control arm angles are slightly different. I am told that you can use some aftermarket arms that can accomodate the angle difference. That and the whole ABS issue, but I'm not sure what to do about that toehr than disable the system.

TNT said:
BTW he has a ZJ.
BTW what makes you so much more knowledgeable then everyone else?

I'm still a tech for Chrysler. Been working on Grand Cherokee's since they came out.
 
Battle of the tech's...
 
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