Large chunks in differential fluid (no whine)

Jackmove

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Changed the differential fluid at 82,000 miles. I've only had the JKU for about 10,000 miles.

Front - Milkshake and likely water contaminated. Looks like royal purple gear oil was used. Replaced with RP gear oil.
Rear - Mostly clear - looks like it was changed recently. Looks like royal purple gear oil was used. Replaced with RP gear oil.
But I found these large pieces stuck to the drain plug magnet.

There's no whine or groan from the differential on turns. I cleaned up the pieces more and they're gold in color (overheat?). Should I remove the cover and look for damage? Or should I assume I'm ok since there's no noise from the diff?

diff.jpg
 
Changed the differential fluid at 82,000 miles. I've only had the JKU for about 10,000 miles.

Front - Milkshake and likely water contaminated. Looks like royal purple gear oil was used. Replaced with RP gear oil.
Rear - Mostly clear - looks like it was changed recently. Looks like royal purple gear oil was used. Replaced with RP gear oil.
But I found these large pieces stuck to the drain plug magnet.

There's no whine or groan from the differential on turns. I cleaned up the pieces more and they're gold in color (overheat?). Should I remove the cover and look for damage? Or should I assume I'm ok since there's no noise from the diff?

View attachment 124094

If they were stuck to the magnet then i'd check the gears, it's not normal to have chunks in the diff.
 
Definitely do an inspection. Although you don't hear any noise, it may not be the contact edge of the teeth those pieces came from. There may be some lateral play or travel that is taking pieces off the corners or edges. Much easier to fix now before you start hearing noise.
 
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Yes, per the factory build sheet, I have a "Next Gen Dana 44 HD Rear Axle" with the Limited Slip Differential.
I would say "Welcome to the Club", but that would be mean 😁

Yeah, just pull the cover and do a thorough inspection. Should be obvious where the pieces came from and go from there.
 
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Pull the cover. Chunks of loose metal are pretty much never normal. I predict further repairs in the near future.
 
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I would say "Welcome to the Club", but that would be mean 😁

Yeah, I'm pretty bummed to have to rebuild the rear this early. The front axle seals (interior of the front differential) are leaking, too. I didn't expect to have to pull both diffs before 100k. :rolleyes:
 
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put these in the front axle when you do your seals..
Thanks for the suggestion. Did you need a special press to get those fitted?

Front diff fluid had water in it and I speculate that it came from the axle seal since my breather tube was mounted fine. Did lots of water crossings and mud bogs over the winter before I realized I had a seal leak.
 
Thanks for the suggestion. Did you need a special press to get those fitted?

Front diff fluid had water in it and I speculate that it came from the axle seal since my breather tube was mounted fine. Did lots of water crossings and mud bogs over the winter before I realized I had a seal leak.
No special tools needed. They push right in the tube, maybe a tap with rubber mallet. Use some RTV on them during installation.

I would say don't be tempted with the cheaper competitors. They have 3 O-rings instead of the molded rubber as shown in the link. I've read comments that they start spinning in the tube.
 
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Yeah, I'm pretty bummed to have to rebuild the rear this early. The front axle seals (interior of the front differential) are leaking, too. I didn't expect to have to pull both diffs before 100k. :rolleyes:
66K here, and I had to do my front axle seals as well as replace the spider gears. Seems quite common for the casting of the spider gears to crack. Though, I did not have to actually replace them because there was no whining, and no noise or meshing issues, I just did it for good measure. Every generation of Wrangler had their flaws, unfortunately.

@HDRyder Ive been told an experienced off-roaders here in the NE that those "seals" are a gimmick. Water and grit still gets past and builds up in the axel tubes. Keeps rocks out but the seals at the pumping are what keeps the gear oil in and clean. When grit gets trapped and the water escapes, you get a clot of crud in the axel tubes. Happened to me.
 
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@HDRyder Ive been told an experienced off-roaders here in the NE that those "seals" are a gimmick. Water and grit still gets past and builds up in the axel tubes. Keeps rocks out but the seals at the pumping are what keeps the gear oil in and clean. When grit gets trapped and the water escapes, you get a clot of crud in the axel tubes. Happened to me.

Could happen I suppose, I'm giving them a try. I think a key may be a pump of grease before each trail day.
 
Anyone know if Lucas gear oil has LSD additive pre-mixed? Or do I need to add it?

Lucas 75W-90 Synthetic Gear Oil 1 Quart
https://www.autozone.com/greases-an...-75w-90-synthetic-gear-oil-1-quart/612866_0_0

The label says it contains a "premium additive" but it doesn't necessarily say the additive is for LSD. On the right it says it's "excellent for use in limited slip differentials."

I used Royal Purple last time and the bottle said that it contained the limited slip additive already. Doesn't look like my local shop has the additive in stock.




 
Anyone know if Lucas gear oil has LSD additive pre-mixed? Or do I need to add it?

Lucas 75W-90 Synthetic Gear Oil 1 Quart
https://www.autozone.com/greases-an...-75w-90-synthetic-gear-oil-1-quart/612866_0_0

The label says it contains a "premium additive" but it doesn't necessarily say the additive is for LSD. On the right it says it's "excellent for use in limited slip differentials."

I used Royal Purple last time and the bottle said that it contained the limited slip additive already. Doesn't look like my local shop has the additive in stock.




Edit: On the other hand, I've only driven about 100 miles since I changed the gear oil. Maybe I should just re-use the royal purple I just put in, despite the risk of contamination.
 
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Edit: On the other hand, I've only driven about 100 miles since I changed the gear oil. Maybe I should just re-use the royal purple I just put in, despite the risk of contamination.
So, you're draining it because you're dropping chunks of metal. Do you really think it's a good idea to reuse the chunky style gear oil?
 
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So, you're draining it because you're dropping chunks of metal. Do you really think it's a good idea to reuse the chunky-styl gear oil?
The damage has already been done. Stop living in the past. "Chunky-style" gear oil is a stretch; the gear oil was changed 8 days ago.
 
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