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Rebuilding T shift questions

joshua

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My kit didn’t come the shims to set preload. I didn’t realize this. I’m at like 1/1.5 inch pounds on the rear output shaft. It has drag, but not enough according the wrench. None of the shims are real thin from what was on there, so I know where this going already. Take one and it will be 50 inch pounds.

I do have a J shift sitting on the shop floor I picked up from somewhere. I’m thinking about disassembling that to see if it has any thin shims to replace one of my thicker shims in my T shift. I think I should have probably twin sticked the J case, as of now I’m learning it is more reliable after the twin sticks are installed. But from memory my T shift worked like a dream and the J was a complete mystery. I wanted the lower gears for these mountainous Great plains of southeastern Minnesota as I’m sure you know of.

I can not find the instructions on JB FABS website. I do not need to put any parts from the JBFAB kit installed inside of the case right? I can just rebuild it and leave out these (pills) I have pictured correct?

The rebuild kit did come with an idler shaft, do you guys use the Chinese ones or stick with the og? At least the bearings a from Japan.

Kit comes Tuesday from JB. Since I have the J shift should I just rebuild the t shift to stock to sell, and return the twin sticks (assuming that’s even possible) for J shift sticks? And just get a rebuild kit for J shift and twin stick the J? I guess I’m asking, is it that much more reliable/better twin stick operation than the T shift? One big bummer JB is closed for a week. So this takes 2 more weeks out.

I know there’s a way to put both cases together. But I can’t seem to find any threads on it. Is it as simple as putting the J rails into a T box? Although I think the gear shafts are different. Probably why they use different bearings. Hopefully I can use the T shift case if I wind up combining, as you can see I’ve already put a ton of work into the T shift case. But I’m sure not. I’ve never had either box apart until a week ago so idk.

Ok I’m going to take that J shifts life for now to go get those shims. Then I can say if been in both. Lol
 

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joshua

joshua

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Well there wasn’t shims on top of the Speedo gear of the j shift. Does it look like they put them under that gear? And I think these gears in the J might be done. I may have made the right choice with the T shift.

J shift teeth are the first pictures teeth/spline T is the last picture
 

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joshua

joshua

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No shims. Dang it!


Edit:

I found them. But I took my thinnest shim out and put the Js thinnest shim in, and now it’s at 14 inch lbs. Man I hate this part.
 
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DirtDonk

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While they’re both apart, maybe make a note of how many teeth/splines on the speedometer drive gears.
Might not pertain to anything in your case, but it’s nice to know for the future, in case you’re deciding on gear corrections for the speedometer.
 
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joshua

joshua

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While they’re both apart, maybe make a note of how many teeth/splines on the speedometer drive gears.
Might not pertain to anything in your case, but it’s nice to know for the future, in case you’re deciding on gear corrections for the speedometer.
Good call!!!!!
 

Oldtimer

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The choice is 6 or 7 teeth. They came in solid steel, or plastic with steel center, like in picture of your J-shift above.
The plastic gear likes to come loose from the knurling on the steel center. If you have the option, use solid steel gear.
 
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joshua

joshua

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The choice is 6 or 7 teeth. They came in solid steel, or plastic with steel center, like in picture of your J-shift above.
The plastic gear likes to come loose from the knurling on the steel center. If you have the option, use solid steel gear.
I have the steel one and it’s 7 tooth. Now
I can look back to see what it is lol
 
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joshua

joshua

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Anyone have any input on the idler shaft? Keep original or use the new Chinese one?

I just went ahead and bought JBFabs shift rails.
 

Viperwolf1

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Anyone have any input on the idler shaft? Keep original or use the new Chinese one?

I just went ahead and bought JBFabs shift rails.
The idler shafts do tend to wear under the roller bearings. If you can feel or measure this wear you should replace it.
 
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joshua

joshua

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The idler shafts do tend to wear under the roller bearings. If you can feel or measure this wear you should replace it.
Ok. I’ll check it really well. I’m sure I’m not unique, but anything precision I’ve ever gotten from china never seems to work out well.
 
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joshua

joshua

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The idler shafts do tend to wear under the roller bearings. If you can feel or measure this wear you should replace it.
My kit came with 2 of these donuts. I put one in the rear output, does the other one go here. I don’t remember seeing one there
 

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Oldtimer

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One of the parts numbered 7181 in attached PDF is donut shaped. The note says it comes in a gasket set.
1755314631918.png

1755314768896.png
 

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joshua

joshua

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Well the new idler shaft fit very, very tight. I had to pound it in then back over and over, as it kept feeling like it was hitting a wall. But it went in and everything seems to be moving smoothly.

First transfer case rebuild in the books! 🙌 Hopefully it equals the first successful long lasting sting rebuild!


Thanks for the help gentleman!!!!
 
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