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rear diff fluid is brown?

6K views 14 replies 7 participants last post by  spastik monkey 
#1 ·
I'm goin to change my rear diff fluid cause its brown and I'm pretty sure it shouldnt be, my question is, is there something wrong or is it just what happens in time, the fluid level was good, and I'm pretty sure its been changed before cause its got sealer all over it. What fluid is best for these rearends and was reading a threads about a friction additive what about that too?
 
#2 ·
yep limited slip additive and i went synthetic all around 75-140 rear iirc and dont remember front for the life of me.
 
#3 ·
thank you, the front looked real good, good color and no metal flakes on the plug, but the rear had a little bit of flakes on the magnet,just around the outer edge is that anything to worry about?
 
#5 ·
How much gear oil and how much additive do I need to get of each?
 
#6 ·
i think its 3 quarts iirc in each and the additive is just a squeeze tube, about 1/2 pint maybe i couldnt tell ya. I just buy it and put it in there.
 
#7 ·
Where do you buy your gear oil and additive from and what's a good brand?
 
#8 ·
I used Royal purple with good results without additive and no chatter.After hearing neg stuff about RP I went to AMSOIL and there additive and got a little chatter on slow turns.I now use Mobil1 LS with Ford additive and the chatter is gone.My truck seems to have a very positive limited slip.I did research the amsoil on the net afterthe fact and found significant amount of complants on Toyota's limited slips using Amsoil.
 
#9 ·
You might as well clean your abs/vss sensor too.
 
#10 ·
Agreed. The ABS sensor is a huge magnet that picks up tones of flakes. The fill plug doesn't do much any debris collection. Those metal flakes on the ABS sensor can also throw the ABS light on the dash.
 
#11 ·
It does stay on a little longer then normal lately when I start it
 
#12 ·
Well I just found out I have an open diff. not a ls.
 
#14 ·
I got some Mobil 1 synthetic.
 
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