black sludge comes out of differential?
07-02-2009, 05:19 PM
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07-02-2009, 06:09 PM
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the fluid that came out of my rear differential looked a big like dark gray/black sludge. is it supposed to look like that? the front differential looked like oil when it drained, it had a bit of the sludge on the drain plug, but the fluid that came out was clear.
just refill it with the new fluid? (mobil 1 gear oil)
08 4x4, 16,000 miles, 1st change
just refill it with the new fluid? (mobil 1 gear oil)
08 4x4, 16,000 miles, 1st change
Last edited by husker_shoe; 07-02-2009 at 06:12 PM.
07-02-2009, 06:13 PM
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How much metal was on the drain plug magnet? If there wasn't much, just refill it. Mine had quite a bit of metal on them from the factory. I changed them at 500 miles for the hell of it just to get some synthetic in there. I now have 5.13's and they too had a bit of metal after 500 miles and the fluid looked bad even though it was just a few weeks old. Unless you got a ton of metal of alot noise, don't worry about it
i ended up taking the whole cover off and spraying it down with brake cleaner. since the oil that came out of the front was so much cleaner than the rear. the front had less shavings and only the plug itself had the sludge on it.
how much gear oil do they take? i read the writeup, and it says 1.35qt - and i could only fit 1qt in there. it was spilling out after 1. and i haven't filled the rear yet, letting the rtv set
07-02-2009, 06:16 PM
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the face of the plug didn't have much, the little pocket around the face was full of little shards.
i ended up taking the whole cover off and spraying it down with brake cleaner. since the oil that came out of the front was so much cleaner than the rear. the front had less shavings and only the plug itself had the sludge on it.
how much gear oil do they take? i read the writeup, and it says 1.35qt - and i could only fit 1qt in there. it was spilling out after 1. and i haven't filled the rear yet, letting the rtv set
i ended up taking the whole cover off and spraying it down with brake cleaner. since the oil that came out of the front was so much cleaner than the rear. the front had less shavings and only the plug itself had the sludge on it.
how much gear oil do they take? i read the writeup, and it says 1.35qt - and i could only fit 1qt in there. it was spilling out after 1. and i haven't filled the rear yet, letting the rtv set
07-02-2009, 06:49 PM
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the fluid that came out of my rear differential looked a big like dark gray/black sludge. is it supposed to look like that? the front differential looked like oil when it drained, it had a bit of the sludge on the drain plug, but the fluid that came out was clear.
just refill it with the new fluid? (mobil 1 gear oil)
08 4x4, 16,000 miles, 1st change
just refill it with the new fluid? (mobil 1 gear oil)
08 4x4, 16,000 miles, 1st change
My original stock rear diff fluid looked nasty as well, there are several others who have had the same (and some threads with pics), not sure what the reason is with the factory fill coming out like that though. My front also looked like fresh oil to.
07-02-2009, 07:58 PM
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Is there any brake in on the gears before they come off the line and get filled?
If the brake in oil is what remains until you change it out at 15,000 miles, that explains the oil appearance.
Anyone know if the factory gear oil is dyno or synthetic?