tail shaft leaking

[kully 560]

hello I have a 1983 280zx turbo that is a automatic and my transmission output shaft is leaking! I replace the seal on the out side of the tail shaft with a new Nissan and it held up for few weeks and now it is leaking again. anybody have suggestion where to go next for this fix . thanks kully

[Mike]

It may require a new seal on the back-end of the transmission.  Did you take any photos while you had the shaft removed?

[zKars]

If its failing that quickly it is likely a defect in the driveshaft surface that rides on the seal. You have four options

1 replace the seal again, but don’t put in in as far as last time. Ie put the seal lip at a different point on the driveshaft surface.

2. use a speedi-sleeve. Google it. 

3. replace the driveshaft yoke so you get a fresh seal surface

4 polish the driveshaft sleeve to remove the defect.

 

Edited December 15, 2019 by zKars

[kully 560]

I polished the drive shaft yoke, but  it did not have any defects at all but shined it up anyway.  I do not know if there is a inner bearing or inner seal? I used the factory Nissan seal and it looked different than the one that came out probably a later design. so I will remove it again and change it  but should I use a different brand seal , is there any inner seals , I did not see any when looking in the end. I will also look up about the speedi-sleeve ,I think I know what there are.

[Patcon]

2 minutes ago, kully 560 said:

I polished the drive shaft yoke, but  it did not have any defects at all but shined it up anyway.  I do not know if there is a inner bearing or inner seal? I used the factory Nissan seal and it looked different than the one that came out probably a later design. so I will remove it again and change it  but should I use a different brand seal , is there any inner seals , I did not see any when looking in the end. I will also look up about the speedi-sleeve ,I think I know what there are.

How many miles on this transmission?

[Zed Head]

8 minutes ago, kully 560 said:

I polished the drive shaft yoke, but  it did not have any defects at all but shined it up anyway.

Seems like it might not be the seal.  There are other leak areas.  Got a picture of the tail housing, with the dripping oil?

[kully 560]

 no I did not take any  pictures because when I removed the original seal it was tore up or worn out around where it meets the yoke. so I thought this would be a good fix. the seal does bottom out when I tapped it in the tail shaft housing. I also installed it dry  and I did not think it needed any grease. could there be a better brand seal than Nissan. after I installed the new seal it was dry under there until I put about 100 miles on the car now it slings around because of the yoke spinning. it is not a bad leak just when the car sits for several weeks in the garage. but I hate oil leaks and this is something I need to fix. the oil will blow back the  rear differential and it make it look like I have a leak there now also . I did polished up the yoke with scotch bright pads and there is no rust , pits or anything else. 

[Zed Head]

1 hour ago, kully 560 said:

 no I did not take any  pictures 

I meant now.  It leaks now, right?

Seal quality might affect high mileage but if it's failing within 100 miles then changing to a different brand probably won't help.  Maybe you damaged it during installation, of the seal or the propeller shaft.

No offense, just to give you perspective, but that's a simple job.  What did you use to shine up the slip yoke?  It should be close to mirror finish.  If you left some texture on it that might have damaged the seal.

And, sometimes you just have to do things over, the same way.  Might have got a defective seal.

[Zed Head]

If you do install another seal make sure to put a little bit of sealant around the edges.  If somebody scratched the seal mounting surface in the past (or you, maybe), you could have a leak around the outside of the seal.

[kully 560]

yes zed head it leaks right now. yes it was a simple job once I was able to undo the drive shaft bolts 1 had to be cut off, and I ordered all new ones to replace and I did anti size them so the hard part is over. I used a scotch bright pad to shin up the yoke it was not mirror like sort of dull metal looking but after 45 years  it did not have any surface rust or pits . it just started leaking a little about a year ago and slowly is getting worst not buy a lot but I can tell when I move the car out of the garage I need to correct this problem now. the seal I took out was tore up where it meets the yoke maybe from age who knows but it was bad. I believe the old seal had a spring around the inner part of the seal and the new Nissan did not have the spring inside anymore, was it a design change later ?? yes maybe I should use a little seal sealant this time, I felt no scratches at all that is why I installed it dry . the flange looked like new but the seal was damaged must have been for a long time and now it has started to leak. I find it funny the shape the old seal was in that it took so long to start leaking. that's why I thought there might be another seal in there that I am missing.

Edited December 16, 2019 by kully 560

[kully 560]

well I think I found why there is a problem with my leak . I ordered this seal nos oem Nissan part and it does not have the internal spring around the rubber lip. I check on line with Timken and national brand seals and they have the inner spring which will kept it tight around the yoke . my Nissan brand must have been missing the part or there was a problem and the aftermarket company improved with the spring. so I will pull out the seal again and change with the Timken brand and really look over the yoke again and if I see any concerns I will order a new yoke and u joint . thanks for the help, and I will post how the up date fix went.