Is this new gear sound normal or not?

Steelyace

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Finished installing new 5.13 gears and lockers in a Dana 44 and a 30, went great with the help of some very very knowledgeable members of this forum and some great videos that are available(both were invaluable).

After finishing the 44 I took it around the block(4 miles) and notices a VERY slight "gear" noise when I let off the throttle and coast at a little higher speed. I pulled it in and went forward with the 30 and contemplated if it was a concern or not. The 30 went great, just like the 44, just slow as I took my time and work gets in the way occasionally. Fast forward to today.....took it on the same little trip and it's probably not as bad as I thought it was originally but it is there. Also when I engage the front axle I believe I hear a little bit on that axle, but only when it's engaged and coasting. Maybe I'm being hyper critical, as I tend to do that after working on something like this for the first time.

Now my question is....is this normal? I am more than willing to drain the rear and confirm my settings but I recorded them and sure they are as close to perfect as I could make them. Is this something to be concerned with? Should I just go through the break in period?

On another note...going from 3.73 to 5.13 (with an automatic and 35" tires) makes this jeep feel like a completely different jeep and that was just a short 4 mile road drive.
 
What was your new gear break-in process like and is the new gear lube a synthetic or a conventional?

I have 80W-90 conventional in there right now and I haven't been through the break in period yet. They literally only have 6 mi on the rear and 3 on the front. If I thought there was a concern I would rather open them up now than do a complete break in and have that gear mesh incorrectly for the first 500 miles, that was my thought process.
 
If your pinion depth was set correctly (have a to pic of the pattern?), your backlash was set in spec, and your pinion preload is correct then I would run it. Noise comes from improperly set up or cheap gears (what brand did you use?).
 
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If your pinion depth was set correctly (have a to pic of the pattern?), your backlash was set in spec, and your pinion preload is correct then I would run it. Noise comes from improperly set up or cheap gears (what brand did you use?).

Revolution gears. Preload was set @17 with about 190 ft/lbs of torque. Backlash was 7. And I will include my final pictures of the setup. That is with 54 thou of shim for the pinion.
I am more than happy to open back up if I need to, doesn't bother me in the slightest.

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my only experience with regearing is from several youtube videos that I just watched in the past couple days primarily because I think I need bearings and want to do it myself.


Your last picture shows a decent view of the driven side of the gear teeth which matters more than the more sloped side.

From what I see there the gear pattern is not quite deep enough into the teeth (too close to the face?) and a bit too close to the inner diameter of the ring gear (toe?)

Here's a 2+ hour video I watched yesterday. This guy seems to know more about differentials than actually making videos but I think his info is at least OK. Much better than a few others.

For some reason I can't get the media link to work but here it is:

https://www.youtube.com/live/2UkWl4xMigQ?feature=share
And if anyone feels he's off on anything please let us all know
 
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I understand what you're saying. If you take a look at the second picture you can see kind of the ghost pattern that might help some. Yes I'm towards the edge but I'm utilizing pretty much the whole tooth. For reference this is 51 thou.

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The very slight hum I hear when coasting? Again, I'm probably being hypocritical. Nothing to be concerned about at this time? Maybe it will go away after the break in.
 
Just confirming you got 19 in/lbs, not 19 ft/lbs.... And that you in fact have pinion pre-load shims installed before going to 190? 🤷🤷🏼😂