rear diff fluid
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Should be 75/140 Synthetic, Do you have limited slip?
Cargo Master
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From: Ardenvoir, Washington
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From: West ID
I just used the Mobil 1 synthetic 75w-140 in my 99, it has the LSD additive already in the fluid and it's been good to go in mine. I believe Walmart carries that, but any other auto parts store will have it. Make absolutely sure it's synthetic 75w-140, there's a tag on the diff that states synthetic fluid only.
Post Fiend
Joined: May 2009
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From: Pea Ridge, AR
You will likely have to look at the tag on the cover to find out if it is LS, but the supertech is just fine to use. If it rumbles a little when turning pick up some LS additive and add a little at a time till it doesnt any more.
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hopefully i can still read the tag. So if it doesnt say limited slip then i dont have to worry about the additive? If it does maybe ill look for some 75/140 with the additive in it.
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From: West ID
I think a lot of them have LS, especially if it's a 4x4 "Off-road" or FX4. If you don't have LS then you won't need to worry about additive, but I do think a lot of synthetics come with the additive blended in.
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From: Damon (South East Texas)
I just used the Mobil 1 synthetic 75w-140 in my 99, it has the LSD additive already in the fluid and it's been good to go in mine. I believe Walmart carries that, but any other auto parts store will have it. Make absolutely sure it's synthetic 75w-140, there's a tag on the diff that states synthetic fluid only.
My truck has the Offroad Pkg, but didn't come with a LS rear diff. I upgraded to a Tru Trac, which doesn't require the additive also.
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i just have 4x4 no off road package or anything. i could only read one tag on the diff it said to only use 75/140 synthetic. i looked on the door and by i didnt see anything that had ls by it. just k/31/9 by the axle part of the sticker. so im assuming i dont have have limited slip?
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