Transfer Case Sparking and Smoking

dutchman

KI7KSV
Location
Boise, Id
I need some help in determining why my toyota j-shift transfer case was smoking and sparking when I was testing it after getting it installed on my 4runner yesterday. Here's what happened: With the help of Kevin (thanks again) I was able to swap out my not working multimode t-case and put it the manual j-shift case. The case seemed to shift and spin just fine before it got put on the truck, though I didn't take the case apart to inspect the internals. After we got it installed and bolted up, the case became VERY difficult to shift. I did fill the case with the recommend 1.2L of 75w90 gear oil. I was able to located 2wd and decided to do a test to make sure everything was working ok before I put all the interior pieces back, throw my tires on and go for a drive. With the vehicle supported on jack stands and shifted the tranny in drive and gave a little gas. Sticking my head under the truck (not completely, just below the door frame) I thought I could hear the t-case spinning roughly. I went back in the cab an noticed some smoke coming from the top of the t-case where the shifter goes (see pictures). I repeated the test this time sitting in the drivers seat. This time I was sprayed with sparks coming from the opening where the shifter goes.

Here are my thoughts:

-The j-shift case has two shift rails. One for 2wd to 4wd selection (top rail in pic I believe) and one for 4hi to 4lo selections (bottom rail in pic I believe). It seems the sparks are coming from the 2wd to 4wd shift rail.d
-I believe these cases can be shifted on the fly (2wd to 4wd) as long as you're under a certain speed. Please correct me if I'm wrong. If that is the case I would expect there to be some sort of synchro-mesh type unit (like a manual trans) that connects the 2wd-4wd shift collar to the 2wd gearing and 4wd gearing.
-To me it looked like the sparks and smoke are coming from that collar/synchro connection.

My Questions:
-Does anyone have any idea what I'm describing?
-Is it best to buy another case and replace it?
-Or, should I have this one rebuilt? What would that cost? Can anyone recommend a shop in Layton/Clearfield?

Any insights will be greatly appreciated.

Plan:
Pending the insights I get from you guys I'm planning on dropping the j-shift case today or tomorrow if I'm able to muscle it out. I then plan to either take it to a shop to be rebuilt or if I buy another one I'll take it apart and try and figure out what's wrong.

Pictures:

It's hard to see, but it should give you an idea where the smoke and sparks where coming from.



 
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