Ford 9" Oiling and Drain ?s

[Caver Dave]

Dropped a back trussed, 5.12 + spool, disc'd 9" under the Moss recently.
To get the pinion & "shovel" (pinion guard) out of the dirt, decided to go double-Cardan driveshaft and point the pinion at TC output... 22* up.
This brings oiling concerns...

A few folks indicate they jack the arse-end WAY up, effectively "leveling" the chunk, and filling to fill hole... multiple quarts over stock capacity.
Others just overfill... assuming a gallon+ of gear oil will negate pinion bearing oiling issues...

Still debating on a drain plug... while I don't "want" to pull the chunk & mop the remaining 2qts of gear oil each time, but spider sense says of a bottom/rear drain plug is mega-vulnerable on a trail rig... am I over thinking this?

So, what are the collectives thoughts on the amount of gear oil, any "mods" to help pinion bearings, and potential drain plug?

1 of the axle seals is wet, along with the chunk, so have have new Set 20's & seals to go in, along with reusable "gasket", so happy to address any needs while down.

 

[Bebop]

No matter the drain plug location, fill in the proper amount of oil the manufacturer recommends.

How often do you drain your diff ? Pulling the shafts and chunk in an offroad rig at least once a year is never a bad idea anyway. I don't see you changing the oil more often than that.

 

[Jody Treadway]

Agreed with @Bebop about pulling chunk to inspect.
But another option for a drain plug would be a guard around it. You can buy weld in bungs with a recessed allen bolt. Install it and then cut a 1/4" thick of heavy wall tube and weld around the bung as a guard. Kinda what Toyota does from the factory. Put it to the side a little so it's less prone to damage.
For filling, you can add a fill plug at whatever level you deem appropriate and make that the new fill line.

 

[Caver Dave]

fill in the proper amount of oil the manufacturer recommends.

That's part of my crux! Recommended fill is 2.5 quarts, which assumes the low-pinion 9" is flat and not angled upward at 22*... which puts the pinon 4"-5" HIGHER, less likely to hold oil slung from ring?

 

[Bebop]

I think you're over thinking it.
Just add a fill plug on top so you can dump the proper amount and send it.

 

[Black Bear]

Why not a big fill plug up high and where you can look in to inspect. use a vacuum pump to pull fluid out?

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[Caver Dave]

I think you're over thinking it.
Just add a fill plug on top so you can dump the proper amount and send it.

"Proper amount" was also in question

Why not a big fill plug up high and where you can look in to inspect. use a vacuum pump to pull fluid out?

Definitely a 2 birds/1 stone solution... should be much safer up high and be tons easier to vac, than thru the fill hole/and having to route around the internals to bottom?
Plus, I have a decent vac pump left over from doing oil changes on jetski...

 

[NCJeeplover]

Why not a big fill plug up high and where you can look in to inspect. use a vacuum pump to pull fluid out?

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I do this with my toyota axles, although not as nice, cause toyota.... Also because toyotas have a habit of loosing ring gear teeth with sticky tires.