HOW GEAR OIL?

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legopnuematic

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80W-90 GL5 is what I have in my 79 and the 14b sf I built for a friend. Both have Yukon Dura-grips in them and that is what they recommend.
 

ali_c20

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80W-90 GL5 in my K5 12 bolt with limited slip and my C20 14bolt ff with open diff.
 

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The fill plug on those covers are not to be used as a level plug. The original fill/level plug is to be removed, and filled until fluid comes out of the hole in the housing, not the cover.

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I wonder how many axels are out there filled with too much gear oil because of these aftermarket covers and the purchasers thinking more is better
 

Bextreme04

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I wonder how many axels are out there filled with too much gear oil because of these aftermarket covers and the purchasers thinking more is better
The location of that hole and that guys statement he put 1-1/2 gallons in frightening. I can imagine those axle tubes are completely filled with fluid if that's true. I bet those axle seals aren't going to last long and there's gonna be about a gallon of 80-90 that will come pouring out of whichever seal fails first.

Personally I run the 75-90 Valvoline in most of my rear ends. Its a GL-5 and is easy to put into everything since it comes in the bags and you can get them from Walmart for ~$10/qt
 

Grit dog

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I wonder how many axels are out there filled with too much gear oil because of these aftermarket covers and the purchasers thinking more is better
At least one! Lol
You could probably spot the rest of them with oil leaking out the axle seals and rear brakes smoking!
 

Old Guy Bill

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Way back we ran short track, 1/4 & 3/8 mile street stock cars.
A Ford 9” was the perffered rearend. We’d weld a tall 1” vent about half way on the left side axle tube, then put a gallon of gear oil in it… this insured that the carrier bearings & ring/pinion gear stayed lubed throughout the race.
 

Strick

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I wonder how many axels are out there filled with too much gear oil because of these aftermarket covers and the purchasers thinking more is better
Be on the lookout for the "spell-check" police with your spelling of AXLE...
 

Camar068

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Be on the lookout for the "spell-check" police with your spelling of AXLE...
I could make that mistake, thats the correct spelling of my grandsons name.
 

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