differential fluid techinacal question

[DewRunner]

My rear diff has a rounded plug and im going on a road trip friday, and i just swapped out the rear seal and so i lost a little fluid in the process, i was told that i could fill it from the top, through where the breather hose goes, i tried taking that off and its getting all crazy and im lazy and im working on rocks and snow.

question is can i send gear oil down the breather tube? will it go threw the breather noozle thing? if i remember correctly it wasnt anything special just a fitting peice not like a one way valve, i have an extended breather to my gas filler cap.

thanks for the input
Lee

 

[JeremyH]

I know that it is easier to just send fluid down the breather tube, but it would be best if you could fill it from the plug. When you use the fill plug, you are forced to not overfill the diff with fluid. Just fill it up until it reaches the bottom of the fill plug hole (assuming that you perform this task on level ground) and then reinsert the plug.

If you overfill the diff, fluid will start to come out of the breather tube and axle seals and you will have a mess on your hands.

Here is a write-up on the task:
Click Here

 

[DewRunner]

well im not going to get my plug out anytime soon, it is a round plug that had a star pattern in the middle and now its round in the middle to, i know what your saying, i just want a little extra fluid in there for the trip, im not going to put a whole bottle of fluid in just a little, ive been driving it around just fine but its only at probably 1/2 to 2/3 capacity

 

[JeremyH]

Yeah, you need to fill it up or else the pinion bearings and carrier bearings wont get proper lubrication and run the possibility of seizing.

I understand about a stripped bolt (the star pattern bolts are called "torx") and if you dont have another option, then go ahead and put it down the breather. Make sure you take the air lock off the top and to pour slowly.

 

[DewRunner]

im asking if i can run it down the breather tube its self

theres not much space under the runner and im having a hard time working under it, i have a gravel driveway thats part dry part mud and the rest snow

i have an extended line breather line up to the gas tank door.

 

[JeremyH]

Yeah, you should be fine running it down the tube.

Like I said, remove the air lock (the white plastic part shown in this picture):

and the fluid should run right down the tube.

It might, however, build up right above the nipple (where the tube attaches to the axle) just because of the design of the attachment, so I would pour the fluid slowly.

 

[DewRunner]

mine has one of these, the one on the left

and i took the metal peice off and put a rubber hose

 

[JeremyH]

Yeah, it should have the metal piece on the left attached to the axle (screwed directly in), then a long piece of rubber hose, and then, the piece on the right (which appears to be the breather...just keeps gunk out, but lets air escape) at the other end of the rubber hose.

 

[DewRunner]

well i did the breather extension a while ago it has a little peice of shop cloth taped on haha for air filtration. i dont have on of those things maybe i should invest
thanks i hope it works

 

[JeremyH]

Good luck!

Keep an eye on the breather tube and make sure that it doesnt start to spit fluid out.

 

[Stick Figure]

why not just find a shop to weld a nut to the outside of the plug and fix the original problem all together.

 

[JeremyH]

why not just find a shop to weld a nut to the outside of the plug and fix the original problem all together.

That is a good solution to the stripped filler bolt problem. I have used this method before with good success.

 

[GottaBeTRD]

can i use your post for this?

I crawled under my truck this morning because i too am planning on doing the rear differential breather extention mod however when i got under there this is what i saw. do i already have one? is that hose on the top the extention?? thanks

ahhhh i hate rust!!

 

[legokcen]

Have you tried to remove the rounded plug with a pipe wrench?

 

[DewRunner]

i got it fixed, its all good.