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Leaking Differential Vent Hose?




I just had my dealer take a look at my Av, which was leaking some type of lubricant. From looking underneath, it was leaking from somewhere above the arm on the driver front wheel.

I got it back and was told that the differential vent hose was mis-adjusted. Apparently it was facing down so the dealer fixed it by rotating it up or some such... the mechanic I talked to wasn't too specific.

I've done (very little) research on differential vent hoses, since I have no idea what it is myself. It looks like when it leaks, it tends to indicate a more serious problem than simply facing downward. Does anybody have experience with this problem?

My truck is an '02 Z-71 with only 3k miles.

Thanks for any help,
I to notice a leak up front and have not had a chance to get this in and looked at. It did not seem to be that much but any amount should be looked at. I will need to get this in . Please keep posting and I will let you know what they tell me as well. I to have a 02 Z71.
I have not had any leaks (that I know of), but in reading my Av manual, I need to check the fluid levels of the front and rear axle, as well as the differential.

Is it tough to get under the Av to check the fluid levels? It looks like I would have enough room to crawl under. I doubt the local oil change place checks these kinds of fluid levels, and if they did I don't think I would trust them since the fluid level dimensions are very specific for the Av.
The vent hoses are on both front and rear diffs as well as the tranmissions (standards and automatics) these are to allow the units to breathe (a place for air to go as fluid expands so seals are not blown out. They should always be directed upward with the opening well above the units. If they fall down it can cause a leak either from fluid expansion or a siphoning effect as air exits. They also should have a vented cap to prevent water from entering easily. Hope this helps ;)
SOME minor leaking from the vent hoses is quite normal. Without the vents you can blow out seals if there was expansion. This is indicated in your owners manual that it is a normal condition. The owner's manual also states that if you drive through deep water and cover the differentials, they should be checked for contamination and refilled if necessary.

Hope this helps!
I would like to add a note to this . I had my rear vent tube and breather changed under warrenty do to the fact it is ti small and can not breath proper under heavy loads ( a 4000lb trailer) I burnt all the oil in the rear end because of this somthing to consider
Thanks all for the quick replies :) Looks like this is something I shouldn't be worried about after all.

Thanks again everyone
This was an issue about 7 months ago...you may want to do a search. It was a common problem that the vent hose on many Av's had bad seals. My dealer had to put a new one on and I have had no problems since.