NP 208 transfer case leak, '85 K5

Subzilla

Subzilla

Test Driver
Joined
Jun 13, 2011
Location
Triad - Mt. Pleasant, Concord & Georgeville
Thought I was fixing a leak that was showing up at the tail housing/output shaft by replacing the seal. Test drove it and there still appears to be fluid coming from the end of the output shaft at the u joint flange and not out of the seal. This has the splined output shaft that slips in and out of the TC. Is there some sort of vent in the end of the output shaft? This thing is now extremely rustproofed underneath - don't need anymore.
 
Sounds to me like me case is overfull of ATF.Pull the fill plug,the top one,and see if anything comes out.I had a 205 one time that would do the same thing and turns out the seal between the case/trans was bad and was letting fluid pass thru.Theirs also a bushin in the tailhousing that might be bad and letting fluid pass thru.
 
Just drained the fluid and readded to change out the seal so I know it's not overfull. Drove about 20 miles after the seal replacement and it's leaking again. I don't think I'm losing transmission fluid to the TC but I will keep an eye on that. That thought did cross my mind.

I filled the TC back up to the level of the fill opening. Is the fluid level above the output shaft seal when it is full? Never really paid attention to that.
 
No, the fluid level isn't above the rear output, it slings it around and also has a pump inside of it. I'd bet on the tailshaft busing being worn out and not holding the slip yoke tightly any more. That lets it ride at a slight angle and is probably why it still leaks a little. You can grab the driveshaft and push up and down to see if it moves inside the transfer case more than it should.
 
In the center of the yoke their may be a then metal disk behind the u joint if so that could be the source of the leak and it may even have a little vent hole in the center that the fluid could be coming from.

Buckeye Performance Inc.
828-779-2242
 
what chris said, mine leaked from the plug in the end of the yoke(behind the ujoint)
i pulled it apart and tried to fix it but everything i did just made it worse. i ended up buying a new shaft because i was lifting it anyway. if i remember correctly, the yoke wasn't readily available so i just waited for my new shaft.
if it's the yoke it will most likely be slinging it in a line directly above the joint (on the body), if it's the seal or bushing, it is usually a drip.
 
Yup, mine has the vent hole. So if it's leaking from here, sounds like the solution is to replace it according to Lee?? What is behind the vent disk? It's not dripping at the seal area but definitely slinging from around the ujoint yoke. Thanks for the info guys!!
 
Back
Top