8 inch rear gear oil question

Discussion in 'Technical' started by x72COMETx, Mar 17, 2017.

  1. x72COMETx

    x72COMETx Member

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    Hello All,

    i just bought a rebuilt 8 inch third member w/3:55 gears, i was wondering what is the best gear fluid to run in it and how much should i get? also are there any additives i should pick up as well

    Thanks, Kyle
     
    x72COMETx, Mar 17, 2017
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  2. yellow75

    yellow75 MCCI Oregon State Rep Supporting Member

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    Probably get a bunch of different answers but if the third member set up is some kind of trac loc unit (posi trac) then you should run a tube of friction modifier in it. I personally just use 80-90 weight gear lube but just picked up some yesterday and see that they have the stuff with modifier in it or at least thats what the bottle leads you to believe
     
    yellow75, Mar 17, 2017
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  3. Crazy Larry

    Crazy Larry Member

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    Valvoline 85W-140 conventional (not synthetic). That's what Currie recommends.
    Limited-slip needs a friction modifier additive.
     
    Crazy Larry, Mar 17, 2017
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  4. 71gold

    71gold Frank Cooper Supporting Member

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    street/strip...ask the people that built the chunk what to run if they are standing behind it...:yup:
     
    71gold, Mar 17, 2017
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  5. groberts101

    groberts101 Member

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    Like the guys already mentioned. If it has clutches in it then use a friction modifier. And i usually care more what the mfgr of the parts has to say than what somebody bolting all the parts together thinks. Could be a worldclass builder putting it together but the mfgr of the parts is the one who stands behind the parts involved. No follow recommended directions?.. no warranty.
     
    groberts101, Mar 18, 2017
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    Crazy Larry and mojo like this.

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