Preferred Differential Lubricant

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mrdap

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Hello Team,
Just wondering if there's a consensus on the preferred or best differential lubricant, both posi and open.
The applications would be:

14 bolt 10.5 full float posi
14 bolt 10.5 full float open
Dana 60 front, I believe it's open
GM 10 bolt rear posi
GM 10 Bolt 8.5" Front, also I believe it's open

My apologies if this has already been discussed.
Thanks
 

mrdap

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Hello Again,
Any other recommendations?
I was looking for a specific brand recommendation if anyone has one.
 

SquareRoot

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Hello Again,
Any other recommendations?
I was looking for a specific brand recommendation if anyone has one.
Hello Again,
Any other recommendations?
I was looking for a specific brand recommendation if anyone has one.
How much you want to spend? Walmart brand or Royal Purple. The world is your oyster.
 

Bextreme04

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I have the walmart brand 80-90 in the 14BFF/10 bolt and NP205 on my square. Its a GL-5 rated gear oil, and everything looks/works fine for several years now. I have a Grizzly locker in the 14BFF. I've hauled several tons of all kinds of things and also towed our travel trailer for several hundred mile trips and had no issues.

I use the Valvoline 75-90 synthetic in the 10bolt G80 rear end on my 2011 Suburban.. also works well and no complaints. I had it all apart and rebuilt the front/rear with a re-gear on them at ~200k miles and the clutch packs and everything on the 10 bolt still looked great. I use it as my wifes daily driver and we also use it for long family trips and towing our 6500lb travel trailer.
 

Doppleganger

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I bought a case of Amsoil HD gear oil for mine. Reviews were pretty highly rated.

fwiw....synthetic will leak easier than conventional. I had to use the Permatex gray gear gasket maker to stop any weeping.
 

fast 99

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To me brand doesn't matter as long as it meets the OEM requirements. We used to use Shell synthetic; it was fine along with NAPA. I buy whatever is cheapest and changed it out once a year or 50k.

edit, was much cheaper at a farm store that's where shell was available.
 
Last edited:

bucket

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I tend to buy cheap (store brand) 1 and 2.5 gallon jugs from the farm stores.
 

mrdap

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I have the walmart brand 80-90 in the 14BFF/10 bolt and NP205 on my square. Its a GL-5 rated gear oil, and everything looks/works fine for several years now. I have a Grizzly locker in the 14BFF. I've hauled several tons of all kinds of things and also towed our travel trailer for several hundred mile trips and had no issues.

I use the Valvoline 75-90 synthetic in the 10bolt G80 rear end on my 2011 Suburban.. also works well and no complaints. I had it all apart and rebuilt the front/rear with a re-gear on them at ~200k miles and the clutch packs and everything on the 10 bolt still looked great. I use it as my wifes daily driver and we also use it for long family trips and towing our 6500lb travel trailer.
Thanks for your feedback!
 

mrdap

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C/K_Lover
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350/454
I bought a case of Amsoil HD gear oil for mine. Reviews were pretty highly rated.

fwiw....synthetic will leak easier than conventional. I had to use the Permatex gray gear gasket maker to stop any weeping.
Thank you for your feedback!
 

mrdap

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C/K_Lover
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C20/K30/V15/V2500
Engine Size
350/454
To me brand doesn't matter as long as it meets the OEM requirements. We used to use Shell synthetic; it was fine along with NAPA. I buy whatever is cheapest and changed it out once a year or 50k.
Thanks
 

mrdap

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Joined
Jul 15, 2012
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Location
USA
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C/K_Lover
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81-91
Truck Model
C20/K30/V15/V2500
Engine Size
350/454

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