Front Pinion Seal leak "fixed" by extending the front diff breather up to firewall

[timer00]

My front diff driveshaft pinion seal was leaking for a while and also my front diff breather hose in its stock form kept getting "gook" in it.

After cleaning the area and opening the fill hole on the front diff to air it out and even after cleaning the front diff hose but putting it back stock again the leak would come back within about 10-15 miles.

So I had this thought about all the built up pressure and how I would get a long drip out of my fill hole enough that I have the lay a pan underneath to catch it slowly coming out.

I just did the extended diff breather mod yesterday. Extended rear diff hose up near gas filler cap as a few have done.. tee'd transfer case and tranny hoses and ran up to engine firewall for their own breather hose.

Then ran the front diff breather hose separate to the engine firewall with a 1/4" clear fuel filter instead of the brass cap and insert.

Even since then I have been around 20-25 miles and not a drip from the pinion / driveshaft area. The day before I really let the fill hole drip out til it stopped and the level was below the hole slightly and extended the hose all the way up at the time also.

I figure I had too much fluid in there either because I overfilled the front diff slightly on my birf rebuild.. or it was drawing in some moly from the knuckles due to blocked breather hose. Meanwhile all the built up pressure I assume was pushing it out around the pinion seal.

By adding the breather hose and letting the excess fluid out I think I may have it licked at least for a while I hope

 

[AF Sergeant]

interesting...i'll have to research this further. I too seem to have developed a pinion oil seal leak. Started as wetness and quickly progressed to a nice steady leak. Will have to get under there and take a closer look. Let us know how it all holds up.

 

[timer00]

interesting...i'll have to research this further. I too seem to have developed a pinion oil seal leak. Started as wetness and quickly progressed to a nice steady leak. Will have to get under there and take a closer look. Let us know how it all holds up.

Well my breathers seem to be working great, I think it was a combination of clogged breathers and slightly overfilled diff that made it leak.. I really let it drain to just below the hole for an hour or so the other day because I could still see fluid in the pinion seal area but it wasn't leaking like before and now I let it really drain out and have the breathers extended its totally dry and has stayed dry for a few weeks or so. My rear diff was overfilled too and I let that drain maybe 1/4 of a quart.