[Rayban33]

Fuji Univance TX15A Transfer Case Rebuild

I am starting this thread to document my adventure with a TX15A Transfer Case drop, rebuild, and re-install in my 2006 Nissan Titan SE King Cab.
I bought the truck from my neighbor approximately 4 years ago. Due to a medical condition he could no longer get up into it. He had a work vehicle he drove most of the time. The truck was 6 years old with 45K miles. I bought it for $8,000. I found out later that I got it for less than half of book value. Although he had general maintenance done, he was not "Kind" to it. I started to get a pretty good "Clunk" in the drivetrain. I would experience it when I did a "drive, reverse, drive" 3 point type maneuver. When I started going through fluid changes of the Diffs, Transmission, and Transfer Case, there wasn't a whole lot of fluid in the case. No abnormal metal shards on the drain plug. There was a small drip coming from the case itself. I had a couple of loose bolts. It seems pretty common. Regardless, it needed a fill. The extent of the problem became apparent once it was brought to level. It was spraying all over the exhaust "Y" pipe. A smell I don't want to experience again anytime soon. Post 2: so what now?

 

[Rayban33]

So, what now? Fuji Univance TX15A Transfer Case Rebuild

To set the stage:

1. I have a Genetic problem that prevents me from paying people to do most things in my life. In most cases, when I do pay someone, the problem is not fixed, and I do it anyway.
2. "What one man can do, another can do". Am I that "Another Man"? We will see (as I have not pulled the case yet). I am going to tell you what I am doing, as I do it, not a historical "happy ending" story. I might look good, or not so much. If the truck ends up on a flatbed half apart (together) you might never hear from me again.
The transfer case is pretty specific to Nissan and/or Titan. It is hard to find rebuilt case or rebuild kits. I have found some "With experience". The lowest mileage case I have found is 77K for $450. It would carry a 6 mth. warranty. If you are into reading the fine print, you get the warranty after replacing all of the seals. Huh? I a have seen posts with failures at 25K. Post 3, the game plan: :eek_surprise:

 

[Rayban33]

The plan: Fuji Univance TX15A Transfer Case Rebuild

Refresh or rebuild?
My case may not be a "Prime Candidate" for rebuild. It may equate to giving a poor eating, heavy drinker, 3 pack/day smoker, a heart transplant. So be it, that is what I have. You may see me have to turn a blink eye to a couple of loose tolerances. It may remind me of a girl in knew in....
The "Rebuild" kit, part number BK505 @ $260 was the only one available. I have seen it from several sources with the same part number and price. The kit may not contain "Had to get parts", but does contain common wear parts. I can't wait to see what "Hard to get parts" may not be included. I tried to build a kit on my own through Rock Auto and others. I suspect that it contains about $100 in parts. I will see what I get and try to cross the component part numbers to National or readily available stuff. There are at least 2 sets of needle bearings that I can only find through Nissan. These may fall into the "Hard to get" category. My kit will be delivered tomorrow.
Thanks to a post in the site, I made my way to the Nissan documentation site. For my 1 day subscription for under $20 I was able to view (or better) every page available for my truck. I will include text and picks related to pulling and rebuilding this thing.
Post 4 - Pre-drop prep, custom tools.

 

[Rayban33]

TX15A Trasfer Case Rebuild-complete

Well, I have rebuilt my transfer case and it is back in the truck. Getting it out was no small feat. Everything was held in pretty good with what I am now calling: "New England Loctite", AKA corrosion. I have not been posting updates because I have been spending every spare minute on this. I will write the whole thing up. The stars weren't in alignment on this one. My rebuild kit was anything but. Some parts were no longer available from Nissan, or anywhere else. I will list every part number.

Do you have a persistent leaking seal on your main output shaft, even after replacing it?

 

[GalaxyPro4X11]

Re: TX15A Trasfer Case Rebuild-complete

Well, I have rebuilt my transfer case and it is back in the truck. Getting it out was no small feat. Everything was held in pretty good with what I am now calling: "New England Loctite", AKA corrosion. I have not been posting updates because I have been spending every spare minute on this. I will write the whole thing up. The stars weren't in alignment on this one. My rebuild kit was anything but. Some parts were no longer available from Nissan, or anywhere else. I will list every part number.



Do you have a persistent leaking seal on your main output shaft, even after replacing it?

Nice job, in for more info

 

[Rayban33]

Transfer Case leak at the output shaft (to rear diff.)

I am going to throw this in my TX15A transfer case rebuild thread because all of the other posts on this seem to be pretty old. This was also a discovery during my rebuild. The "Postmortem" dissection of my case revealed that it was hemorrhaging from 2 places. The rear main seal, and the 3 bolts talked about many times here. The three bolts: one was missing entirely, one was finger tight, the last seemed to be ok. This setup (to me) is a poor design. The bolts hold the oil pump assembly in place. The pump housing is aluminum, and is trying to shift each time you change the shaft rotation (drive--> reverse, and reverse --> drive). Steel bolts going into a aluminum plate with the torque speck of 25 foot lbs, or so (don't quote or use this number.). leading into a case full of juice, is just begging to come apart. It uses washers much like the "Crush" ones on your fill/drain plugs. New washers, a squirt of gasket sealer, and some nice Loctite "Red" (never to come apart again), and you are good to go. But, that is not what I am writing about. You have a pressed bushing at the rear output of your case (to rear diff). It is not shown in the exploded view, and carries no part number. Nissan states: "If it is bad, buy yourself a new half a case". Well, that is $440 at discount, and I am guess you couldn't get it anyway. I found a small machine shop in Ca. selling nice Brass bushings for $29. I would like to tell you that you could replace this without cracking the case open. Bushings scare me. I have made some transform into "Short and Stowt" when they put cam shafts into the center of your V8. I grant you that seals wear. They wear really quick if what you are trying to seal is not true (loose in the caboose). See pics of old and new bushing.
Can be purchased from: Omega Machine - https://www.omegamachine.com/pdf/Nissan Titan extension housing.pdf

 

[SmackIt]

This is a really interesting thread, I compliment your story telling ability. However.... you never provided any of the details you promised.

What was in the BK505 kit? What wasn't in the BK505 kit?
Where are all the part numbers you mentioned you would share.
No pictures of what you found inside?

" I would like to tell you that you could replace this without cracking the case open " What does that mean? You can, you can't?

" The rear main seal, and the 3 bolts talked about many times here." What 3 bolts (picture?), talked about where ? Link to a thread.

You're a great storytelling writer, you just left out ALL the details that would make this an epic thread.

Thanks for the link to the bushing.

 

[Rayban33]

Years later update: Fuji Univance TX15A Trasfer Case Rebuild

It's been quite a few years since I started this thread. I did, and STARTED documenting my transfer case rebuild mostly because it was one of the few things that I couldn't find on the internet. I felt an obligation. However, as mentioned above, it could have been epic. What I didn't do was to finish it. I still have the truck. I am going to go through my notes, and pictures, and finish this thing. I will try to keep to the topic, and keep the "Story Telling" to a minimum. It has been quite a few years since I did my rebuild. If nothing else, pay attention to this:

After removing the transfer case, grab the input shaft, and rear output shaft. Twist them in opposite directions. If there is a lot of play (clacking), chances are that your planetary gear nest and/or front case section (the outer ring locks into the aluminum case) are shot. It is not worth rebuilding what you have. My transfer case has not leaked a drop of fluid since rebuilding it. It does contain lots of aluminum though. It is like a silver slick in the fluid.

My case has tons of "Slop" now, and isn't far away from total failure. I will most likely find a good core, and use the parts I can from what I have now. Again, sorry I dropped the ball on my thread. I am going to try to write my rebuild up correctly for everyone.

If you are going to rebuild your transfer case, you will need the instructions found in the NISSAN manual. Unless things have changed, you can gain access online for a small fee (1 day subscription) and get the PDF(s) you need. this is not a small job. You will need a good selection of snap ring pliers, and a bearing press.