black sludge comes out of differential?
07-02-2009, 03:22 PM
#1
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black sludge comes out of differential?
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
07-02-2009, 03:24 PM
#2
I would give it a serious look over before just refilling it. It should come out like dark oil, not as a gelatanous glob of sludge. Your front sounded about right, not your rear.
07-02-2009, 03:26 PM
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07-02-2009, 03:32 PM
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Broken ring or pinion gear teeth, spots on the teeth with gouges or serious wear marks.....basiclay anything that doesn't look normal (i know....what is normal). Seriously though, a little metal residue is normal from the break in and wear of the gears, as is black or seriously used/abused oil.....but alot of sludge is usually an indicator of something wrong.
07-02-2009, 04:43 PM
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What did you use to flush it out with? I used a couple cans of contact cleaner because of the high evaporation rate with no residue. I also used the red high temp RTV.
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07-02-2009, 04:50 PM
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sprayed brake cleaner in there. used a blue RTV. letting it set now.
is it really bad if the cover slid when i put it on? i don't want a leak and i dont' want to do this for another 18,000 miles....
is it really bad if the cover slid when i put it on? i don't want a leak and i dont' want to do this for another 18,000 miles....
07-02-2009, 05:04 PM
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As long as there is RTV around the whole cover, it should be fine. When you tighten up the bolts, it will squeeze out the bead of RTV. If you have no gaps in the RTV, it will be fine.
07-02-2009, 05:10 PM
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it squeezed out, and i had a good sized bead, so hope it'll be alright. what a dirty job. even orange clean is having a hard time getting this crap off of me. and to think i was going to change the diff fluid on my grand cherokee. another time, lol
