how much diff fluid?
It's a Van Gogh
Joined: Feb 2010
Posts: 7,813
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From: Elk Grove, CA
Be sure to fill on a level surface. If the truck is facing down a slight incline it will surprise you and overflow at slightly less than 3 quarts. Then you'll bump your head scrambling for the drain pan and kitty litter. And you'll still have to turn the truck around to get the rest of the oil in. Happens to people all the time. 
9 ECHO 1
Joined: Aug 2009
Posts: 12,467
Likes: 58
From: Missouri
Or an oil with the LS friction modifier in it. You dont want to do both or you will go from limited SLIP to limited GRIP.
Post Fiend
Joined: Feb 2008
Posts: 10,977
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From: Lancaster, Pa.
Great observation. I do have to say though I used Royal Purple 75-140 with the friction modifier already in it and had minor scuffing turning, had to add about a half a bottle (2.5 oz) of the friction modifier to sooth things. Me personally I'd go with the straight synthetic gear oil and add the modifier seperate, what I'm doing on my next change at 200,000.
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9 ECHO 1
Joined: Aug 2009
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From: Missouri
Interesting. I used the Valvoline synthetic with LS added and have had no problems, and the LS has always gotten me out of trouble.
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Post Fiend
Joined: Feb 2008
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From: Lancaster, Pa.
Valvoline is some good stuff, although I have it in my tranny, Vavoline max life. Yep, kinda puzzled me also because RP marketed their use of friction modifiers pretty heavy in their gear oil. I literly added minucule amounts (F-M) till I had no scuffing, things have been just right the last 87,000 now. Originally changed at 100,000.
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Elder User
Joined: Dec 2010
Posts: 704
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thanks guys!!! pulling both axels for painting (CAT YELLOW, red diff cover,black bolts) and other stuff doing leveling or 4in lift (adding 2 extra leafs to each side) riding on bump stops as of now gotta go 5inches up on front to level, pinion seal on both and opening front to check bearings i deffentaly got something wrong, not the axle shaft u joints or hub bearings thos checked out fine new U-joints all the way around maby ball joints
using amsoil BTW
using amsoil BTW
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Elder User
Joined: Dec 2010
Posts: 704
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hahaha iv been waitin for someone to to something funny about that lol was gonna do camo, ya im wierd i know.... i had a 4x4 mudder with a lime green engine and axels, purple trans burnt orange transfer case white/red candy cane drive lines
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