Engine/Transmission (1998.5 - 2002) NV5600 Still Leaking

[chazj]

I had the transmission seal replaced at a driveline shop. The new one still leaked. When I took it back, the mechanic didn't understand why it was still leaking as the seal replacement is quite "basic". He is going to warrenty his work and re-do the job.



I am curious is there is something "unusual" about this job that may explain the continued leak? I have read about a transmission vent... and am curious that if it were defective/plugged up... could it force fluid past the transmission seal?



Any input is appreciated.

 

[JKinney]

I replaced mine last march and it was seeping again a few weeks later, but not as bad as when I replaced it.

 

[SSolderitch]

I had the floor & exhaust wet when I bought my truck - never a puddle. So I replaced the seal myself. Did a check a few hundred miles later. Still some wetting on the floor brace. It looks like it is grease slinging out of the ujoint caps when they heat up. The seal & tail shaft are bone dry.

 

[FYarcho]

From your sig I assume you have a 4X4 and you are talking about the seal on the back of the transfer case where the drive line comes in. If this is the case then your tans vent wouldn't have anything to do with it, because they are both sealed independently of each other. I cant remember but I believe there is a vent on the transfer case. The trans has a vent as well it is at the rear of the trans. It is just a small pipe with l loosly crimped on cap as you can see from pic. I don't have any pics of transfer case



View attachment 67286

 

[chazj]

From your sig I assume you have a 4X4 and you are talking about the seal on the back of the transfer case where the drive line comes in. If this is the case then your tans vent wouldn't have anything to do with it, because they are both sealed independently of each other. I cant remember but I believe there is a vent on the transfer case. The trans has a vent as well it is at the rear of the trans. It is just a small pipe with l loosly crimped on cap as you can see from pic. I don't have any pics of transfer case



View attachment 67286

Attachment 67286[/QUOTE

As it was explained to me, the oil is coming from the transmission past the new seal on the trans output shaft that connects to the transfer case.

Thus my question as to whether a plugged up vent on the NV5600 could force the oil thru the seal.



Truck is going in next week to get fixed again. Mechanic going to take an extra good look also to see if any of the shafts might be slightly burred (from the factory) to have caused problems with the original & replacement seal.

Guess we'll see what happens...

 

[wcjp]

Check the shaft for burs and play. Also, is the shaft actually round? Mic it at several points.

 

[Misenheimer]

Hi

I have had the same problem with seals over the years and have discovered that if I use scotch bright to break the glaze where the seal ran it would not leak after replacement. It must be kind of like honing a wheel cylinder. I had the most problems with crankshaft seals that use the flywheel as the seal surface. 600 grit sandpaper and oil will do the same thing. Also lube the seal with whatever it is trying to keep in. The drip will quit after a while but ti is annoying to put in a new seal and have it still drip.

Hope this helps

 

[Bunyan]

If you overfill the transmission, T-case or diffs you will have seepage at the seals.

 

[FYarcho]

I hope your mechanic is replacing the right seal. The output shaft seal on the trans is on the inside of the tail cover. So I am concerned when he says it's "quite basic". Simply because it is quite an undertaking to replace that seal. The tranfer case, and crossmeber for the rear of the trans must be removed. Also the Tail housing must be removed to replace the seal. Which in my opinion is quite a job. Trust me I've done it!!.

 

[FYarcho]

Sorry about that you know I was thinking about the input shaft. Now that I think about it the seal can be replaced without taking the tail cover off (my bad). What I can say is that these seals are pretty fragile when it comes to intallation. If not careful they can be damaged by pounding them in with a hammer or such. If they get damaged and out of round just slightly it will continue to leak.

 

[chazj]

I hope your mechanic is replacing the right seal. The output shaft seal on the trans is on the inside of the tail cover. So I am concerned when he says it's "quite basic". Simply because it is quite an undertaking to replace that seal. The tranfer case, and crossmeber for the rear of the trans must be removed. Also the Tail housing must be removed to replace the seal. Which in my opinion is quite a job. Trust me I've done it!!.

He did replace the seal and (so far) no leaks.



He specializes in driveline & u joint repair/replacement & also rebuilding transfer cases. He did have to remove the above to get to the seal and as a plus I got new fluid in the t-case replaced... . twice... Oo.

 

[FYarcho]

Sweeet Glad everything worked out

 

[JKinney]

I used a seal removal tool reached in the tail piece and plucked it right out and set a new one in