Question on the Dana 30 HP pinion preload adjustment

TexasTJ2004

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I have found that there is too much of the play in my front (HP Dana 30 from XJ). Basically I see little bit of up and down and in and out movement, and the pinion seal is leaking.
I am getting prepared to adjust the preload, which I believe is the cause for the issue.
Wanted to get some feedback on the steps:
1. First I will check the torque on the pinion nut. My understanding is that since it not crush sleeve but shims, the torque should be in the area of 210 feet/pound.
2. If adjusting the torque works (all play disappears), then I found the problem, I can replace the pinion seal and call It a day
3. If the torque on the pinion nit is fine, then I have to start digging into shims.
4. My understanding is that I have to remove the carrier (yeah, brake rotors, unit bearings and shafts all go out), remove the pinion seal and gently knock out the pinion (from back to front towards where carrier was).
5. Then I remove the outer bearing from pinion, take all the preload shims from pinion, measure them with micrometer and note all of them.
6. Then I remove some smallest shim and reinstall the pinion with the shims, outer bearing and start torquing and measuring the preload with this preload wrench. What is the used bearing preload value? Since the bearings are not new, I cannot go by the value of new gear install, which is like 20 inch/pound or something. Do I understand it correctly that the right solution is to have the right preload value when the pinion nut is at 210 feet/pound?
I would appreciate help from folks here, as diffs is the only area that I don't feel 100% confident in.
 
Do you mean the outer bearing? If I start playing with the inner bearing, the one that is pressed onto the pinion, I will need to go through the entire pattern measurement to set the proper pinion depth.
Can I replace just the outer bearing only?
 
Do you mean the outer bearing? If I start playing with the inner bearing, the one that is pressed onto the pinion, I will need to go through the entire pattern measurement to set the proper pinion depth.
Can I replace just the outer bearing only?

You will not have to go through any of that if all you do is replace the bearings. Only time settings change is if you change the settings.

Do you know what is the preload value that I am supposed to have if I don't use new bearings?

6-10 in lb
 
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You will not have to go through any of that if all you do is replace the bearings. Only time settings change is if you change the settings.



6-10 in lb

Got it. Basically as long as I pick up the same model of bearings (inner and outer), the assumption is that their width will be the same and as a result I don't need to change anything in the pinion depth shims.
The issue is that these gears were set less than 10K miles ago. The guy from I whom I bought the axle, reversed it in 2021, barely drove it and then I barely drive it. My assumption is that the bearings should be still good. Also, I don't have a press to press the inner one.
 
Got it. Basically as long as I pick up the same model of bearings (inner and outer), the assumption is that their width will be the same and as a result I don't need to change anything in the pinion depth shims.
The issue is that these gears were set less than 10K miles ago. The guy from I whom I bought the axle, reversed it in 2021, barely drove it and then I barely drive it. My assumption is that the bearings should be still good. Also, I don't have a press to press the inner one.

If it has that few miles on a rebuild I would tear it down and inspect everything. Hopefully it is something simple like a loose nut.
 
If it has that few miles on a rebuild I would tear it down and inspect everything. Hopefully it is something simple like a loose nut.

BTW, I assume that while testing the preload I will use the existing pinion nut. First time when I will use the brand new pinion nut is when I am tightening up everything after verifying everything is set?
 
BTW, I assume that while testing the preload I will use the existing pinion nut. First time when I will use the brand new pinion nut is when I am tightening up everything after verifying everything is set?

Yes the new seal and pinion nut is the last step in the process.
 
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The problem is that the pinion nut actually does not seem to be lose. This means that or bearings are shot, or the shims somehow expanded themselves, or it was installed incorrectly in the first place.

That indeed is an issue. If you turn the pinion does it at least seem smooth or does it feel notchy or rough? It may be that they just put in too many preload shims when they assembled it.
 
That indeed is an issue. If you turn the pinion does it at least seem smooth or does it feel notchy or rough? It may be that they just put in too many preload shims when they assembled it.

I inspected the ring and pinion. All seems not broken at all.
No damage as far I could see.
There were 2 problems with axle so far.
First, it was used with improper pinion angle (3.6 degrees, creating too much stress on the bearing).
Second, the oil in the diff was bad, too much water in it. Looked like just mud.

9B0D0744-D320-4ED9-9A44-B4945238E5AA.jpeg
 
Cannot say I am thrilled with the pattern on those gears for being only 10k old. Part of the is most likely from the pinion not being held tight enough. Good news is that it is the front diff so you can make things better and not worry too much about noise from it.
 
Cannot say I am thrilled with the pattern on those gears for being only 10k old. Part of the is most likely from the pinion not being held tight enough. Good news is that it is the front diff so you can make things better and not worry too much about noise from it.

I don't have manual hubs, so the front will spin every time I drive, and this is my daily. Already bought kit of pinion bearings, shims, new nut, magnetic dial etc, so will have to go through the verification of gear pattern.
 
Just removed the yoke. After I removed the but, the yoke just came off with 0 effort, pulling it with just 2 fingers. I planned to use some tool to remove the yoke, but this one just came off
 
Just removed the yoke. After I removed the but, the yoke just came off with 0 effort, pulling it with just 2 fingers. I planned to use some tool to remove the yoke, but this one just came off
Check its fit on the pinion spline after it is pulled and the face of the yoke where it contacts the bearing.
 
Also, the inner bearing looks good.
Now I need to check the yoke, measure the shims and start removing, and then tightening with the old nut.
My question is the following:
Let’s assume that the pinion depth is good. Then I play with shims (start removing) till I get the preload of 6 to 10 inch pound when tightened to 200 feet/pound? After I hit the right shim amount and width, with right preload , then I install back the carrier and verify the pattern with gear marking compound?
Let’s say the Pattern is good, then install the seal, tighten the new nut, verify preload and call it a day?