Transfer Case Leak Fix

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Mar 21, 2007 | 12:44 AM

powrstrkr

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From: Rio Rancho NM

Transfer Case Leak Fix

My 86 manual 1350 has a very slow drip coming from the front DS seal. It's not critical yet but it'll need attention soon. Is this seal replaceable w/out removing the case? I have a spare 1354. Could I use part(s) from it or should I buy whatever I need new? I'm guessing it's a rubber seal that's wearing out.

Mar 21, 2007 | 01:46 PM

HappyJack

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From: Wichita, KS

The front out put is different on the 1354 than it is on the 1350. The 1354 would have the replaceable seal behind the yoke. I am not sure on the 1350. Non of mine has ever leaked. I just cleaned and greased the splines and snaped the boot back on. I have read that there is an internal u-joint in the front of the 1350 but have never had one apart. I would guess that the seal is internal also.

If you swaped in the 1354 you would need to change your front driveshaft. And most likely the shift lever. You can see the shift lever differences on my web site under "shifters". If your 1350 has the long, bolt on lever they will swap by just removing the nut that holds them both on. If your 1350 has the short one peice shifter it will have to be installed in the 1354.

Mar 21, 2007 | 02:30 PM

HappyJack

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From: Wichita, KS

Well I guessed wrong. There is an external seal on the front output of the 1350. Just went out and checked my spare 1350.

Just unbolt the front driveshaft from the front pinion. There is a slip shaft that goes inside the front out put of the t-case. There is a boot that has a clamp securing one end to the driveshaft and another clamp securing the other end to the t-case. I have had good luck using my hands (wear gloves) to pull the boot from the t-case. Leaving the clamp in place. Then when it'xs ready to go back together push the end of the boot back on. Most times it just snaps back in place. With the front driveshaft and boot out you can see the seal. Just pick up as new on from your local parts store. If it's been a while since you've changed the t-case fluid this would be a good time to do it. Remove the lower drain plug. With the fluid drained it may be easier to clean and dry the front output where the new seal will be installed.

Of course put a bit of fluid on the rubber part of the new seal and the shaft it seals. Should be pretty straight forward and easy.

Mar 21, 2007 | 05:13 PM

powrstrkr

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From: Rio Rancho NM

Right on Jack! Thanks. I'm picking up the front seal from NAPA on the way home after work for about $8. I've had that DS out so many times I can do it in my sleep. I'll add it to my list this weekend - B2 water pump, sealant on the trailer deck, ad infinitum...

The shaft wobbles a little at the t-case end. How tight should it be? It's quite a bit looser than either pinion or the rear DS output shaft. I'm wondering if the bearings might be a little worn but it runs and shifts great, and has never made any noise. And I suspect play in the shaft wore out the seal. Could it be normal play due to the spline design? I'd say it wobbles about 1/8in up & down at the ujoint.

Last edited by powrstrkr; Mar 21, 2007 at 05:17 PM.

Mar 22, 2007 | 07:05 PM

kernel-panic

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From: Yokosuka, Honshu, Japan

Sounds like you might as well put new U-joints in while you're at it. Sounds more like they've worn out from lack of lubrication or some such. Does yours have the automatic or manual hubs? I would leave the hubs disengaged until required / replace the automatic with manual ones. I exercise my front drivetrain every so often without going off-road, mostly because I don't want it to break on me on the trails. Just some food for thought, etc.

Mar 22, 2007 | 09:05 PM

HappyJack

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From: Wichita, KS

Quote:

Originally Posted by powrstrkr

The shaft wobbles a little at the t-case end. How tight should it be? It's quite a bit looser than either pinion or the rear DS output shaft. I'm wondering if the bearings might be a little worn but it runs and shifts great, and has never made any noise. And I suspect play in the shaft wore out the seal. Could it be normal play due to the spline design? I'd say it wobbles about 1/8in up & down at the ujoint.

I guess you should try to determine where the wobble is at. Like KP said if its the u-joint then replace that. If it's the male splines on the end of the driveshaft that slides inside the t-case you can check on replacing that. I have seen splined shafts that have a plastic coating and that will wear off and cause play (wobble). Then check the female shaft in the front output for movement. As far as knowing how much play is too much, I guess thats up to you. I'm not bad (or used to be that is) at removing stuff like t-cases or tranny's, but I take them to others that know more than I do to tear them down and work on them.

Mar 23, 2007 | 05:33 AM

powrstrkr

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From: Rio Rancho NM

The ujoints are new. My old shaft, which was stowed after the lift a couple years ago, was resurrected with the D35 swap. Play is in the splines. I'll see what I can see when I replace the seal this weekend. But it's been like that a while so I'm sure it won't cause problems.