Engine/Transmission (1998.5 - 2002) Transfercase to NV5600 leak???

[Sea01Cummer]

I have a small drip where these two bolt together. The oil appears to be trans fluid. That seals these two together??? This is the only leak on the truck and i hate it, it needs fixed now!!



Steve

 

[CumminsPower98]

This is an easy fix at least for me it is. Just pull the t-case and pop in a new rear trany seal. NAPA 19211 or National 710058

 

[JKinney]

Hi Steve



Im chasing that problem too. I noticed oil on the bolts as you have, and it seems to be very clean. Some of mine was comming from the top where the shifter goes in. After tearing that apart it had been leaking pretty good. I will check in the am, as I made this repair about a month ago.

 

[kscheffler]

I have the same leak but I think mine is transmission fluid?

 

[JKinney]

I have the same leak but I think mine is transmission fluid?

Yes where all leaking transmission fluid, the question is from where. Prior to fixing the leak at the shifter I would notice drops of clean red oil on the bottom of the transmission and on the bolts where the transfer case is connected. I no longer have drops but evrything is still wet, I need to get ender the rig with detergent and clean off the oil and see if it returns.

 

[justinp20012500]

Its the red and green seals between the tcase and transmission.



Just make sure your tcase halves are not leaking. All those leaks are an easy fix, its just fixing the right leak that might throw you.



I would do it all while I was in there...

 

[Sea01Cummer]

So there is a seal in the back of the transmission and also one in the front of the Transfercase?? My leak showed up after i did my clutch so it may be the shifter.



Steve

 

[CumminsPower98]

Yes, there are seals on both sides. My t-case seals have never leaked a drop in 311k miles but I have changed the rear trany seal a couple times now. Those seal numbers I posted before are for the rear trany seal. I have replaced the rear trany seals in a couple other trucks too so it's not uncommon at all and is an easy and cheap fix.

 

[Sea01Cummer]

Thank you for the numbers.



Steve

 

[JKinney]

Yes, there are seals on both sides. My t-case seals have never leaked a drop in 311k miles but I have changed the rear trany seal a couple times now. Those seal numbers I posted before are for the rear trany seal. I have replaced the rear trany seals in a couple other trucks too so it's not uncommon at all and is an easy and cheap fix.

I dropped the transfer case a couple weeks ago and replaced the seal, I just went under the rig, there is no oil on the ground, but the back of the transmission is wet again with transmission fluid. My rig sits level, and I did add a 1/2 quart extra of fluid by placing one side of the rig on blocks. I hate to wate all that expensive fluid, by dropping the transmission again. I wonder how many 4 x 4s are actually wet or seeping out of that seal. There is no sign of any transfer fluid leaking.

 

[CumminsPower98]

Make sure you are not getting oil running down from the vent on the right rear of the trany. I don't understand why you would be waisting oil. You don't need to drain either gear box to R&R them. Did the seal maybe get damaged when you installed it? If installed correctly there is no reason for it to leak. I always use a thin film of RTV when I install seals just for added protection in case there is a small scratch or something in the housing the seals are going in.

 

[JKinney]

I was understanding that when you pull the drive shaft out of the transfer case, that it would allow the transfer case fluid to run out, and the same goes for when you pull the transfer case off the transmission tail section. Any how I dumped both last time and changed the seal and noted things were dry for a couple of days. I just went out and cleaned all the oil off and will let it sit and reinspect looking for the leak.

 

[CumminsPower98]

The oil level in both boxes is WAY below the shafts. The only way for oil to come out is if you tip them on end. A little might run out the t-case when you pull the shaft but that's just the little bit sitting in the tail section. Same with the transmission. Only a tiny bit will run out when you pull the seal. The main oil levels are way down below this, even when overfilled. The only time there is oil against the rear trany seal is when you are driving so just letting it sit won't show you anything other then what might keep seeping out from between the trany and t-case that might have gotten past the seal while driving (it pools in there and slowly seeps out the gasketless crack between the two). Hope you get it figured out.

 

[JKinney]

The oil level in both boxes is WAY below the shafts. The only way for oil to come out is if you tip them on end. A little might run out the t-case when you pull the shaft but that's just the little bit sitting in the tail section. Same with the transmission. Only a tiny bit will run out when you pull the seal. The main oil levels are way down below this, even when overfilled. The only time there is oil against the rear trany seal is when you are driving so just letting it sit won't show you anything other then what might keep seeping out from between the trany and t-case that might have gotten past the seal while driving (it pools in there and slowly seeps out the gasketless crack between the two). Hope you get it figured out.

Thanks for the knowledge. Im not in a rush to pull the transfer case again, atleast for a month or so... So I will watch it and make sure that is what is leaking. I have already sealed the shifter box so that is not it.