Rear differential leak help

[laneo9417]

Hi all - I was giving my Ex a quick once over this evening and noticed a fluid leak coming from my rear differential where it meets the driveshaft. After some quick research on this problem I believe this may be a bad pinion seal? Hopefully these pictures can help me out:

I just noticed this for the first time tonight and I believe I caught it early - the leak looks fresh and the spot on my driveway was only about the size of a quarter. I did noticed what appeared to be some fluid on the fifth stabilizer shock that I'm guessing was flung from the driveshaft (you can kind of see this in the first pic). I last drove the car today to work and it ran fine with no issues. First, is this in fact a bad seal or possibly something else? Second, is this a serious issue requiring immediate attention? I was planning on taking the Ex on a mini road trip (150mi round trip) this weekend and I'm wondering if I'll be ok in the short term. I apologize in advance but I am a bit naive when it comes to this subject. Any help from you all is appreciated.

 

[koda2000]

yes, pinion seal.

 

[laneo9417]

yes, pinion seal.

I figured as much. Any idea if this is a big deal? Is it ok to drive with in the short term?

 

[Turdle]

I figured as much. Any idea if this is a big deal? Is it ok to drive with in the short term?

Depending on the size of the leak, it should be ok for a short while.

Be sure to check the vent tube also. If it is clogged it could cause the pinion seal to leak. As the differential heats up the air inside expands, so, there needs to be a vent, or the pressure will make one.

The opposite happens when a hot differential is exposed to water. The rapid cooling causes a vacuum, if the vent is clogged water might be sucked into the differential through the bad pinion seal.

 

[laneo9417]

One morning last June I noticed the vent tube dangling on the ground. I zip tied it back up and had no issues until now. I'll be sure to check that though. Thanks for the insight.

 

[lobo411]

Just keep the differential topped off, until it gets to the point where gear oil is leaking out faster than you can put it in!

I've been driving with a leaking pinion seal for 5 years now. Yes, there's obvious signs of oil leaking from the seal. But in 5 years, I've had to add about 1/2 cup of gear oil. Nothing to worry about really.

 

[Boywonder629]

Yup bad pinion seal, i did mine on my Mountaineer it wasent too bad you just have to be careful to count your turns when taking the pinion bolt off, if you screw that up all your bearing preloads will be wrong and can cause premature gear or bearing wear/failure. If you dont feel comfortable doing this take it to a shop but if you are its a pretty straight forward job just make sure you have a 3 finger puller to get it off then pop the old one out with a screwdriver, and tap the new one in lightly with a hammer making sure its level when you get it in, then reassemble fill her up with fluid and go!! And remeber if you have a trac lock rear axle to use synthetic fluid haha i almost made that mistakeO