242 transfercase leak
 

Alright so I swapped in a 242 in place of my crapped out 249 case, and after some milage and freeway driving it's leaking fluid bad enough to actually get all over the hatch and rear window, sprayed over everything underneath to the point that I can't tell what's what- I cleaned it up and drove it around to find that it seems to be spraying, but not out of anywhere in particular, I feel it may be the output shaft seal, but there's nothing definitive there yet other than what seems to be a spray pattern that follows the rotation in that area...

It's an external slip yoke, and has that stupid metal deal over the seal (I've seen it referred to as an oil slinger).

Anyhow does that metal deal have anything to do with the actual sealing process? I reused the old one, but it was a little beat up while taking it off...just wondering if that's more of my issue or could be a possibility.

Again it's an external slip with the small cone.

Output shaft seal was the culprit.


https://cimg2.ibsrv.net/gimg/www.che...fca2c38259.jpg

I had my 242 rebuilt and the transmission shop tried 3 times to install a seal that didn't leak immediately. Finally I did it myself and saw that the groove on the output shaft was a possible reason for the failures. It will either cut the seal or snag the spring and dislodge it, neither of which you will know has occurred until you take it back off. It is for the snap ring that the slinger bottoms out against and has a fairly sharp edge that the seal has to slide over. A mechanic friend suggested a round file along the edge of the groove to remove the edge, I used a chain saw file that worked well. Also suggested was packing the area around the spring with grease to aid in lubrication and spring retention. From what I have read the grease is not detrimental to the rubber, but I have reservations about that. My first attempt lasted 3 months before leaking and upon removal the seal lip was gone (looked like your picture) and the spring loose on the shaft. Rubber felt hard so I don't know if it was low quality, the grease or whatever. A very thin metal sleeve that can be slid over the shaft past the groove, slide the seal on and seat, then remove the sleeve, is an idea I have if the latest seal installed yesterday fails. I'm on my fifth seal which is the first one bought through the dealership. Better quality perhaps? We'll see.

if you could post a pic of the shaft that is snagging the seal that would be helpful.

i have done several seals on motorcycle forks and other areas of the bike and i always use belray waterproof grease. the reason is standard grease reacts with rubber and can degrade it. but i would expect it to take a long time to damage a seal if the wrong grease was used. the purpose of applying grease is to keep the seal lips from folding in during installation/use which results in a leak. shaft seals typically dont leak once installed for a long time unless there is a worn grove which decreases the pressure against the seal. forks for example travel against the seal and having grease in the seal is important because of the drag tangent to the seal. they tend to leak more frequently.

seal quality between OEM and aftermarket is pretty close IMO, although price may not be. on my TC i used a seal from the factory because autozone did not have it. autozone's prices were about half of the dealer and no leaks so far.