Author Topic: NP208 T Case leaking issue  (Read 1782 times)

Offline 84Silverado4x4

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NP208 T Case leaking issue
« on: October 23, 2017, 10:11:21 PM »
I have had an issue with my Np208 T case leaking for a while and have replaced the tcase all together with another and still have a leak issue.  I have an 84 shortbox with 6" lift.  I have dropped the Tcase slightly to compensate for the lift to help driveline angle and it like to leak at the seal drive shaft slip yoke seal.  Is the lift and angle of the transfer case just going to make it virtually impossible to seal or is there a fix?  I have had two different 208 cases with new seals in the truck and a few different drive shafts and it likes to keep leaking.   
84 Silverado Reg Cab Shortbox 4x4
4" lift with 35's
5.3 vortec, 4l60e, np208, dana44, GM 12 bolt

Online VileZambonie

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Re: NP208 T Case leaking issue
« Reply #1 on: October 24, 2017, 04:29:25 AM »
Make sure the vent is clear
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Offline 101 airborne

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Re: NP208 T Case leaking issue
« Reply #2 on: October 25, 2017, 06:55:35 PM »
I had the same problem with my NP208 and used Lucas trans sealer and it actually worked.

Offline Irish_Alley

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Re: NP208 T Case leaking issue
« Reply #3 on: October 25, 2017, 09:02:56 PM »
is it the seal or the weep hole in the yoke?
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Offline 84Silverado4x4

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Re: NP208 T Case leaking issue
« Reply #4 on: October 26, 2017, 10:49:38 PM »
is it the seal or the weep hole in the yoke?

It's only wet from the seal back but I wasn't aware of a weep hole.  I am using a shaft with a double cardan joint since the angle is pretty steep.  I had a driveline noise with a regular u joint and this took care of it.  It leaks pretty good and coats the underside of the cab and leaves a mess where I park.  doesn't seem to be an issue if I wipe everything up with a rag it stays dry until I drive it again.
84 Silverado Reg Cab Shortbox 4x4
4" lift with 35's
5.3 vortec, 4l60e, np208, dana44, GM 12 bolt