Lots of threads on the intermediate shaft o-ring, I recommend you read those and watch the video as a primer for this.

I recently did two, both had o-rings that were hard as plastic when I took them off. Well known that the steel intermediate shaft wears out the aluminum housing. I recommend using Permatex high torque silicone and coat the big end of the shaft after installing the new o-ring. This helps dampen the fretting wear the shaft causes to the housing as well as sealing against leaks.

I replace the o-ring without removing the shaft. Loosen the nut, counting turns out, leaving one thread engaged, push the shaft forward till it bottoms, remove the nut and push forward gently so as not to drop the intermediate gear and bearings. Replace the o-ring, coat the big end with silicone, then push back in. Put silicone on the threads, install and retighten the nut, turn 1/16 to 1/8 more than original. The sleeve will crush slightly more but will be fine because:
1. The bearings have worn in since the original install to this point.
2. It was not a precise measurement to start with.

Once tight, the big end should be slightly recessed subflush to the case. Coat the big end and the surrounding area with a thick coat of silicone. This will help prevent leaks as well.

This is the silicone I use:

https://www.permatex.com/products/ga.../?locale=en_us

Let me know if anyone has any questions.

@tnrangerover - this is for you.

 

You’re the man. Thanks Extinct! Sounds simple enough.

I’ll be doing this to my new 04 case before install and then the removed 03 case as well.


cheers!

 

Good info. I have a leak at the main shaft and a spare transfer case to seal up and swap at some point. Watching a few videos on this they put a lot of attention on the crush sleeve and measuring the end play? or lash? Using a dial gauge? So you're saying reuse the crush sleeve and go a bit more on the nut is fine.

 

and the "1/16-1/8" is that 1/16"-1/8" or is it 1/16-1/8 of a turn of the wrench?

 

Yes, this. The crush sleeve thing is how they set the preload on the tapered roller bearings. Very similar to how you are supposed to do it on trailer wheel bearings if you have ever done that. Too tight and you burn up the wheel bearings, too loose and it wobbles and wears funny. Anyone who has done trailer bearings knows they wear in after an hour or so of driving and a good idea to snug them down a bit.

On a 20 yo gearbox the bearings have worn in some, so another 1/16 or 1/8 turn brings that preload back to where it was originally.

 

Thanks for this. I didn't realize there was room to push the shaft out the front.

 

There isn't without separating the case from the transmission, but I have done it in the truck without removing it completely. You have to remove the driveshaft and the transfer case mount, then slide it back. I did it with the engine out and slid the transmisssion forward.

 

I'm about to change the int shaft oring engine side so gonna tap it back until I can get at the oring. Now my question for the oring on the nut side. If I continue to tap int shaft back until I can get at that oring, it's gonna drop the int shaft onto it's threads. My question is this. Once I change the nut side oring and I tap the int shaft back through, will the internal gears and collapsible tube return to their original position and the gear float be the same after I tighten the nut back up to it's original location,( I'd be marking the shaft,casing and counting the turns to wind it off obviously)? I get the extra 1/8 or 1/16 turn but will the gearing be all outta shape. The nut side oring is showing very very small sign of leak, but having stripped all out to change the clutch and I'm already in there, that's why I'm gonna change them orings. What do you advise. Thanks

 

Yes, gears will all go back to right location. I recommend using a thick coating of Permatex high torque silicone on the sealing surfaces in addition to the new o-rings. BTW, the factory o-ring is likely to hard like plastic more than rubber. You will probably have to cut it off with a razor.

 

Extinct, many thanks for that. Having not done this job before I'm glad you had the info for me. It's good to talk. Thanks