T Shift & J Shift Interchangeable w/ C4

[jedblake]

Vehicle is a 66 U13. About 10 years back I swapped my I6 3spd with a C4 and J Shift from a 74.
My original T shift had been rebuilt but i just removed and stored since my donor drivetrain came with the later tcase. I also had the later j shift rebuilt at the time for good measure.
Just rebuilt the C4 and curious if the 66 t shift would bolt right up? I always liked the t shift compared with the J for ease of going into gear. Also, any difference in speedo cable teeth I'd change? Are the internal tcase gear ratios different? Anything else I'd have to convert?
I'm mostly street little offroad, daily driver. I do like the twin stick option and really thinking about it if I stay with the j shift
Thanks

 

[sykanr0ng]

You can bolt either case behind the same transmission.

T shift low range ratio is 2.46
J shift low range ratio is 2.34

On a street Bronco how often do you plan on using low range 4wd?

 

[jedblake]

Probably not ever. I just installed a high hp 347, my area is all desert, soft sand, medium grade hills. I assume 4wheel high ratio the same for both model t cases?
Thanks

 

[SteveL]

Pretty sure with the j-shift you don't have to mess with the detents to make the twin stick work correctly.

 

[sykanr0ng]

Probably not ever. I just installed a high hp 347, my area is all desert, soft sand, medium grade hills. I assume 4wheel high ratio the same for both model t cases?
Thanks

Yes, like most transfer cases both are 1:1 high ratio.

 

[Viperwolf1]

Could be a difference in the speedo drive gears between the cases. You can swap rear output assemblies if there is.

 

[Lunar-tic]

Not sure what the exact difference is, but swapping from T to J definitely changed my speedo. Actually made it read correctly with 33 inch tires.

 

[SteveL]

Not sure what the exact difference is, but swapping from T to J definitely changed my speedo. Actually made it read correctly with 33 inch tires.

I'm guessing that depends on what motor the t-case was behind. Probably just the plastic speedo gear to compensate for different rear end gears if it came behind a 6 cylinder from the factory.

 

[englewoodcowboy]

I have had a few clearancing issues with a T shift behind the C4 however most of our customers who we did the swap for ultimately went to twin sticks and they shift much easier. I am uncertain if a C4 ever left the factory behind a T shift, maybe another item for Viperwolfs Mind Your P's and Q's post?

 

[Viperwolf1]

I have had a few clearancing issues with a T shift behind the C4 however most of our customers who we did the swap for ultimately went to twin sticks and they shift much easier. I am uncertain if a C4 ever left the factory behind a T shift, maybe another item for Viperwolfs Mind Your P's and Q's post?

T's were put in behind the C4 until the J's came out.

 

[jedblake]

Thanks guys a wealth of knowledge.

 

[chrlsful]

so if I pull my J offa the adapter, toss it - the T will go on the adapter & will go back on the C4?
T's still in the bronk behind an i6 & runnin (C4 from a long gone '77 bent8). The C4 & J/it's adapter R on the ground pulled apart. I got parts all over, but a running rig.

 

[Viperwolf1]

so if I pull my J offa the adapter, toss it - the T will go on the adapter & will go back on the C4?
T's still in the bronk behind an i6 & runnin (C4 from a long gone '77 bent8). The C4 & J/it's adapter R on the ground pulled apart. I got parts all over, but a running rig.

Yes. You'll need to pull the spud shaft and bearing retainer out of the J and put it in the T before you bolt the adapter on.

 

[chrlsful]

that helps me for when I get there.
Thnx Vip,
locals R clamoring for me to sell them the C4
and the adapter. Don't wanna (I'll loose the "J, tho).
BUT, it'll B yrs B4 I swap in the auto, just gettin goin w/the NV3550
after 36 yrs of 3.03...