14 bolt FF fluid questions

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Grit dog

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^Except for the jack up one side then the other.
If you fill until the oil runs out the filler plug it will get to the hub bearings, especially if the trailer tongue is lower than the rear of the trailer, then it will overfill a bit as well.
It'll reach the ends even more so because the ring n pinion aren't pickin up oil and slinging it.
But yes, filling through the ends works just fine.
 

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^Except for the jack up one side then the other.
If you fill until the oil runs out the filler plug it will get to the hub bearings, especially if the trailer tongue is lower than the rear of the trailer, then it will overfill a bit as well.
It'll reach the ends even more so because the ring n pinion aren't pickin up oil and slinging it.
But yes, filling through the ends works just fine.

Yeah, only one side is needed. It's just the easiest way to get the fluid level higher than the fill plug.
 

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It took less time for me to jack up one side, pull the axle shafts out of both sides, drain all the crud out, ran some sacrificial lube in to be sure, and installed my cover on the drain side when it dried up, and once it was sealed, I filled the diff from the side of the jack up, installed cover, once sealed i set it down. I feel my method ended up causing less work. because i would have to put a diff cover gasket, etc. and now its got new lube, enough to lube it fully. Since I didnt go under trailer I could have just used jack, no jack stand. but i had the wheel off and safety is good. but my method did what it aimed to do and is not leaking, success?
 

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Ok gotcha.
So how’d you get all the old oil out?
 

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Ok gotcha.
So how’d you get all the old oil out?
Drained it out of the other axle tube side. Got it all cleaned out with some sacrificial fluid and put the lower side cover on first, then filled it, then put that cover on, then lowered.

@mcarlo86
this is a thread related to my trailer. what kind of axle is under yours? what is your tongue setup ? springs? What do you primarily use it for? anything cool added on?
 

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^ So still whatever old oil, probably half of it, never came out. Unless you jacked one side up about 3’ higher than the other?
 

AuroraGirl

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^ So still whatever old oil, probably half of it, never came out. Unless you jacked one side up about 3’ higher than the other?
i plan on going back in, because the vent tube is broken and its open to atmosphere. im guessing its where the dirt and water came from.i will be draining from the pan next time to reseal it, then i will fill from the side which has a small weep.

i did have it about 2' higher though, anymore it was a little iffy
 

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Drained it out of the other axle tube side. Got it all cleaned out with some sacrificial fluid and put the lower side cover on first, then filled it, then put that cover on, then lowered.

@mcarlo86
this is a thread related to my trailer. what kind of axle is under yours? what is your tongue setup ? springs? What do you primarily use it for? anything cool added on?
The trailer that was in the headache rack picture is one that my Dad built for my Grandpa back in the 90’s. My little brother has both that pickup and the trailer now. It was an ‘85 C10, so it has a 10 bolt axle. I believe the pickup had the heaviest spring package that a half ton could have been ordered with. He cut the frame off under the cab and used that for the tongue and I believe it had a 2” ball coupler on it. My grandpa used it for hauling branches and leaves, etc from his yard to the dump ground mainly. My brother uses it now for all kinds of stuff. Hauls his riding mower in it, lumber, etc.
 

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