Topic: Diff fluid and cold weather

[Mozman68]

Well, I thought I was just crazy last year in my assumption that the cold weather had something to do with diff fluid coming out of my breather tube, but it was confirmed this weekend.

I didn't drive the Jeep all afternoon on Saturday and all day on Sunday.  Went out to the garage first thing yesterday morning and smelled that familiar smell of diff fluid.

Why would a drop in the temperature cause some diff fluid to come out the breather tube whenthe fluid hasn't been recently changed or modified in any way??

[Jeffy]

Diff fluid gets thicker as it gets colder so if the fluid level is high or there is enough splashing, I guess it could cover the vent and cause pressure to build.  Otherwise, it's the breather or cap causing the restriction and that's causing the pressure to build.

[jagular7]

I'd pull the tube off the diff and blow into it to see if the tubing is clogged. Take another tune (clean) and put it on the diff and blow into it. See if there is pressure that builds up in the diff. If there isn't, then there is another 'relieve' somewhere in the housing.
About the only way I think the fluid is coming up out of the tubing is a cause of the venturi effect. The tubing is too small and the fluid wicks up.

[oldjeep]

My sons comanche used to do the same thing in the winter.  You would come out in the morning and there would be a small puddle on the ground.  Never could figure out what was causing it.