Overfilled differential leaking ?

[Sp6saz]

Hi folks, I've got a question on over filling a differential on a2006 ce 300 international school bus. So if I've done work on the vehicle lost fluid and it still drains out the fill hole when cold and sitting for a week is it a safe bet this differential was way over filled and that's what blew out my wheel hub seal ???

[ol trunt]

Many differentials have a vent hose coming out of the top. If the vent hose is plugged the pressure can cause hub seal failure.
Jack

[magnakansas]

plugged vent, overfilled, bad/damaged/worn out seal, damaged seal surfaces, seal not installed correctly.

OR

a combination of the above

william

[Sp6saz]

Originally Posted by ol trunt

Many differentials have a vent hose coming out of the top. If the vent hose is plugged the pressure can cause hub seal failure.
Jack

Yes, I'm going to verify vent is clear once repairs are done and diff refilled to proper level

[Sp6saz]

Originally Posted by magnakansas

plugged vent, overfilled, bad/damaged/worn out seal, damaged seal surfaces, seal not installed correctly.

OR

a combination of the above

william

Well, I've replaced the bearings I've replaced the seal and the brake shoes and drums but even after losing gear oil from differential on brake shoes when leaking and then removing both Hubs and losing oil again the differential is still over full with oil so I can only assume that it was way over full. Going to drain and refill to proper level tough part is international days in my axle gotta lift a side 6" then wait a minute lower and then lift opposite side in order to get sufficient oil in both hubs then recheck oil level and fill as needed.

[magnakansas]

well, keep us informed about the results please. i have to do what you are doing. not looking forward to it. I will be adding internal tire pressure monitor system

william

[cadillackid]

Hubs? wait are you talking rear or front? ive never seen rear hubs that you fill.. only front and those should have a clear cover or a rubber plug you can pop out when the bus is level..



the rear diff you only fill from the square plug.. yes when the bus is level..

[ol trunt]

Caddi, most old skool full floating axles are lubed from slosh from the differential. Even my 2005 Isuzu 1 1/2 ton uses this technique.
Jack

[cadillackid]

Originally Posted by ol trunt

Caddi, most old skool full floating axles are lubed from slosh from the differential. Even my 2005 Isuzu 1 1/2 ton uses this technique.
Jack

That’s the way I’ve understood it. I’ve never put oil in the rear hubs only the front (oil bath)

[Sp6saz]

Originally Posted by cadillackid

That’s the way I’ve understood it. I’ve never put oil in the rear hubs only the front (oil bath)

Directions via spicer are to fill the differential to fill point then jack up each side of axle at least 6" higher than the other and wait a minute so oil can fill the hub with before driving. And check oil level after jacking each side and fill as needed

[cadillackid]

got it... I guess i never did that step.. i always filled it.. drove it around town a few minutes.. came back, checked it again.. added as needed.. I guess my turnng corners did the same as jacking it up

[Sp6saz]

Originally Posted by cadillackid

Hubs? wait are you talking rear or front? ive never seen rear hubs that you fill.. only front and those should have a clear cover or a rubber plug you can pop out when the bus is level..




Spicer calls for filling the rear hub cavity between the inner and outer bearing race in the rear hub with oil just before inserting the outer wheel bearing on the hub and after install of bearings and seals they say to jack the vehicle axle up 6" higher than the other side for 1 minute and then refill oil and repeat on other side. What I'm wondering is why when I blow into my vent tube which is not blocked I took it off and verified this by blowing through it but when I blew in the tube with it installed the air I blew in came back out as if there was a one way valve or balloon installed on it seems there's more air space than that in there are there Channels in there that could be clogged like are the passages in there that small.


the rear diff you only fill from the square plug.. yes when the bus is level..

^^^^^^^^
Oops see my info above missed this section.

[Sp6saz]

Originally Posted by magnakansas

plugged vent, overfilled, bad/damaged/worn out seal, damaged seal surfaces, seal not installed correctly.

OR

a combination of the above

william

Hi William, so I'm wondering if you know... when I blew in my vent tube with my mouth the air I blew in came out as if it went in against a balloon I only got in a single breath of air. I removed the tube and the fitting it connects to and verified they were clear and air passed through easily is the air cavity in there that small as it seems it would be much larger is there Channels in there like tiny passages that could clog and hold back air

[Sp6saz]

Originally Posted by ol trunt

Many differentials have a vent hose coming out of the top. If the vent hose is plugged the pressure can cause hub seal failure.
Jack

Hi, so I'm looking for as much help as I can get... I'm wondering when I blow into my vent tube the air I blow in comes out as if a balloon is on the other end and that's only one breath but when removed air goes through tube and fitting it attaches to easily are there spaces inside so small in the differential they could become clogged and block air flow

[cadillackid]

the air comes back out because you pressurized the axle cavity with the air you blew in through the vent.. so it will escape when you relerase.. thats good actually.. means the vent can in fact disperse positive pressure..

[Sp6saz]

Originally Posted by cadillackid

the air comes back out because you pressurized the axle cavity with the air you blew in through the vent.. so it will escape when you relerase.. thats good actually.. means the vent can in fact disperse positive pressure..

I thought it would take a lot more air than one breath to fill the cavity in there is all

[cadillackid]

its possible the vent only alows a maximum positive pressure... the vent is designed to let air in slowly when the oil contracts and temp drops but also designed NOT to suck in water.. so it may be you trigger the valve when you blow into it..

[mmoore6856]

one other reason rear ends get overfilled is if it got water in it as driven thru flooded area. this is not common but i have seen it many times in my shop. always loosen the drain plug a bit and see if water or oil comes out i it was sitting . if it been rolling it will be mixed with the oil and will show usually as a grey color. some hubs have a primer port (a plug that takes a hex key to remove) to put oil into the hub so it dont run dry. i have replaced wheel bearings that were not primed and failed. dont hope the oil gets to them make sure it does.

[mmoore6856]

when the hot rear axle gets submerged it cools it off causing a vacuum which helps suck water into your vent. make sure your hose is up high on the frame if you run thru water or launch a boat

[magnakansas]

I would not have expected what you described. The two plug in the differential housing is also something I would not expect. Have you found a metal tag on the axle housing? Not on the differential, the housing. There is something- not usual- going on with this whole deal. I think finding a manual on this exact axle/ differential might clear up some things.

I can’t make enough volume to pressurize a golf cart axle, I don’t see how you can do that to a truck sized axle.

I suppose there could be some sort of check valve. Does the assembly look like it could have some sort of check valve?

William