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Cleaning differential

Discussion in 'Differential & Driveline' started by scenic760, Apr 11, 2021.

  1. scenic760

    scenic760 Full Access Member

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    Hey All,

    I went to go change the oil in my differentials today. the front one looked ok except the fluid seemed pretty dark and there was some sludge on the bottom of the pumpkin I scraped out...the rear one actually started draining what looked like normal fluid then it became a thick almost pudding like substance.

    I'm assuming it's emulsified oil and I scraped as much out with a silicon baby spoon but it looks like there is still some sticking on the pinion, etc...

    I have seen on some forums that recommend running diesel for a couple miles and draining but in my particular case the truck isn't running at the moment. Would it be possible to simply jack it up, fill with diesel and hand rotate the wheels or is that just not going to get enough movement to clean anything? Also I would assume you wouldn't want to fill it all the way so the diesel doesn't seep into the axles?

    Oh...and I found this little gem on the magnet on the cover. It doesn't look like anything is loose, could it be someone simply screwed up and left it in the case in doing something else in there previously?

    20210411_150518.jpg 20210411_150618.jpg
     
  2. Curt

    Curt Supporting Member Supporting Member

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    If you have a way to spray gas,it will clean it up real well.Otherwise use expensive brake clean.Probably about 5-6 cans.

    That piece of metal looks like an oil slinger to me,off the pinion..Not sure what else it’d be.It’s a pinion shim,but also retains oil for the pinion bearings,not letting oil run right back into the case.
     
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  3. Curt

    Curt Supporting Member Supporting Member

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    I guess it could also be a thrust washer out of the differential.Is that a stock differential?
     
  4. Memaloose

    Memaloose Full Access Member

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    Brake Kleen it and blow it with compressed air after you wipe it clean. If there's no slop or broken pieces, call it good it looks good in the photo..
     
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  5. SirRobyn0

    SirRobyn0 Full Access Member

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    I wouldn't be to happy to find a piece of my diff on the magnet like that. But like others have said if It's not giving you any problems I'd probably just run it.

    At the shop we'd wash it out with brake clean and let it dry then reassemble.... If you don't have brake clean on hand you could use a bowl of gas and a brush, it'll just take a lot longer and be a lot messier. And put out your cigarette before hand lol
     
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  6. RecklessWOT

    RecklessWOT Full Access Member

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    Just spray it out with brake cleaner like any other greasy part! You might need to use a full 2-3 cans if it's really that dirty in there but the stuff is so cheap that it's a non-issue. Better to use a little extra than not enough, can't make it "too clean". Hell, I go through probably half a can every time I do an oil change lol. Any garage/backyard mechanic should have a few cans on hand at any time
     
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  7. C10MixMaster

    C10MixMaster Full Access Member

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    spider gear thrust washer???

    Inkedspider_gear_kit__04196.1493669861.1280.1280_LI.jpg
     
  8. RecklessWOT

    RecklessWOT Full Access Member

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    that's exactly what it looked like to me at first, but honestly how does one end up bouncing around inside the diff with the spiders still intact? Did someone really just leave it in there after a repair? If so, I am worried about every single thing that previous "mechanic" ever put a wrench on...
     
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  9. PrairieDrifter

    PrairieDrifter Full Access Member

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    Yeah nah something strange is up, the one time I found a spider gear washer, my diff didn't like it. Granted I found the washer after this lol

    It could be just mixup as well , I tore down a motor at my old job, a Pontiac small block I believe. Goin the through the routine, then I get to the pan, get it almost off and heard some clanking.. uh oh... this was just a tired motor?!? Well got the pan off and turns out there's two brand new rod bearings just sitting in the bottom of the pan.... so anything can happen guys lol.

    3C5B1574-2DCC-4CC2-A6BA-0D69562DBEAC.jpeg
     
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  10. eskimomann209

    eskimomann209 Supporting Member Supporting Member

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    PO ( Previous owner not OP )haggled the diff shop. They left him a surprise. Probably didn’t go down the way the shop wanted. :dancingpoop:
     
  11. scenic760

    scenic760 Full Access Member

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    Thanks for the replies!

    I was wondering the same thing, how a washer would just "appear" in the diff. I'm almost thinking someone was working on the diff and put it in the case to use and forgot about it and went and got another one? And yes Reckless, I have been worried for a while, haha!

    At this point I'm going to get it running and see what happens to everything! Although I did go through the brakes completely, something about 6000lbs of steel rolling down the street and not being able to stop it concerned me...
     
  12. SirRobyn0

    SirRobyn0 Full Access Member

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    The only way your going to know is to pop the spider gears out and look to see if both the thrust washers are actually there. It's not a far stretch to think that a mechanic had one drop out when re-installing the spiders and didn't notice. Would you or I notice, yes probably but someone else who knows. A lot of good mechanics have very little diff experience.
     
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