Dd re-gear fail/pattern check

slow600

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05 Lj with d44 rear. Got frustrated and said fukit after many many attempts, slapped it together with fresh lube and a prayer. Surprisingly low noise, mainly high pitched whine at 50mph at part throttle or unloading the rear. Negligible noise under power or decal above/below that speed.

Need to pull the cover to be sure, but no disco glitter seen through the fill hole. Backlash .007, don’t remember my pinion depth. Started with factory shim under pinion bearing, all subsequent adjustments were under inner race.

Where would you start next if you were a da like me? Pattern was getting better the deeper pinion went (I think), but ran out of shims to get pinion preload where it needed to be. Was set at 14 in lbs.
 

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Is that before you ran it or currently after running it? How many miles?

It looks way deep to me but your transfer is ****... do yourself and anyone else that you're asking for help a favor, and thin out your compound with a couple drops of gear oil. You do not need to slather that **** on.

Hell I'll use one of those white tube's for 4 different installs, you don't need much.

Also run the pinion with a drill, forward and reverse... AND apply pressure to the ring gear while it's spinning, that helps tremendously with pattern lay in and will also make a ghost pattern on the unpainted teeth which sometimes will tell a better story of what's going on.
 
this is before driving, going to pull cover this weekend.

will thin down my compound more, i did apply pressure with my hand holding a leather glove. not sure if this is enough or not.
 
slow600 said:
this is before driving, going to pull cover this weekend.

will thin down my compound more, i did apply pressure with my hand holding a leather glove. not sure if this is enough or not.
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How much has it been driven? Miles?

It's not like you gotta put your whole body weight on it, just some drag.

What gear brand and ratio? OEM pinion shim is a great starting point. Yukon and revolution I've had to adjust no more than 6 thou from factory.

14 for pinion preload is too loose, you'll end up letting the pinion walk which will destroy the gear set.

I'm assuming the pinion preload was checked with nothing else installed, just the pinion and carrier?
 
ive put a few hundred miles on it so far #smart. richmond gear in 4.56 flavor, i did start with oem shims and most likely went wrong from there. i did check preload sans seal.

where is sw mo are ya? im in clever 65631
 
A few hundred shouldn't destroy them if it's out too far.... although the first two heat cycles are the most important for break in and thats within the first hour of driving.

You may always have noise now. Sometimes you just do tho.
 
Pulled the cover. Ring gear pattern looks good, but does seem to have a sharp edge. Some glitter in oil, normal imo.

Unsure if I should start from scratch set up wise, or tighten up pinion preload and run it
 

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Run a pattern on it to double check the wear marks. Still deep, see that sharp line at the root. You don't want any sharp lines.

Sounds like you've made up your mind tho.

Is fixing it easy?, no but if you want to run it, run it. What's the worst that could happen? ...
You gotta buy another gear set and install kit and redo it all... anyhow?
 
I'm not an expert by any stretch of the imagination. Only setup gears half a dozen times. Not saying it won't work but definitely not ideal. Sharp edge at the toe of the ring gear teeth and you're already seeing some flaking happening down there. Metal in the oil seems excessive after just a couple hundred miles. Like I said, no expert but I would have tried to get it better.

I resonate what NDCjeepsmith said though. It could run a long time, or it could fail on you at the most ill-opportune moment.




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way too deep imo, never seen that much glitter in break in. I'd redo it but that's a pretty good wear pattern already on it.
 
Buried the pinion, probably 10–12 thou too deep. Non JK D44 pinion bearing preload is 14-20 in/lbs if I remember my chart correctly so you’re on the loose end but technically still in spec.

My honest opinion is those gears are set where they’re going to be now, run them and deal with the noise or setup new ones and learn from the experience.
 
thanks for the replies. i tore it down over the weekend and set it up again which did include pulling pinion and not shimming as deep. didnt take pattern pics but feel much better about it. i also ran the pinion preload slightly higher at 18lb or there abouts.

havent driven it yet to see if noise is better, went yolo and started in on the mighty 30 instead.
 
Sucks to suck! Pinion bearing started a disco part after attempt #2. now I get to do all bearings again plus bonus outer axle bearings. I always learn the hard way…
 

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