Transfer case options (1 Viewer)

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ksemerdjian

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I am still going over options for my future build and been thinking over transfer case options. My plan is to ultimately have a Orion transfer case so my question is what input gear to go with. I currently have a 71 3 speed transfer case so it has the 10 spline input and pto gear and it will be going on a NV4500. Since I'll be buying an adapter for the transmission anyways is it worthwhile to buy the AA adapter for the 4 speed setup so I can change my input gears to a 16 spline versus the 10 spline
 
I am still going over options for my future build and been thinking over transfer case options. My plan is to ultimately have a Orion transfer case so my question is what input gear to go with. I currently have a 71 3 speed transfer case so it has the 10 spline input and pto gear and it will be going on a NV4500. Since I'll be buying an adapter for the transmission anyways is it worthwhile to buy the AA adapter for the 4 speed setup so I can change my input gears to a 16 spline versus the 10 spline
I hit the post reply button by mistake, I wasn't done. Other than the input gears is there a difference between the 3 peed transfer case and the 4 speed transfer case?
 
Personally would go nineteen spline and switch to a split transfer case. I sure cost for a used split case would be less than an Orion. Options for other gear sets and support from multiple sources.
 
Split case is a great option.
If everything was already set up for an early t-case and you don't want to redo drive lines and the parking brake the Orion is a good choice.
As for your original question, I have had several conversions with the folks at Advance Adapters and they are fans of the 10 spline input shaftt/gear, and point to a common issue that plaques the 16 spline input. It's pretty common to see the spline beat up by the input gear. Personally, if you check the torque on the input shaft nut periodically you won't have this problem.

Otherwise, everything on the Orion bolts up the same. The case is thicker externally in some areas such as around the bottom, near the drain plug.

FWIW, the new AA adapter accepts both t-cases, at least for the 4L60E. It's drilled for both bolt patterns and uses an adapter ring to compensate for the different input bearings.
 
I have considered the split case option but all I have been able to find locally are 1k and up then I still need the low range gears which are about 1k and up from my understanding plus rebuild kit, I figure at the end I'd be in it at about 2.5k which isn't terrible if it's truly worth it.
 
Keep in mind that the split case requires a parking brake solution. Either an aftermarket kit on the back of the t-case or something at the rear brakes.
 
Keep in mind that the split case requires a parking brake solution. Either an aftermarket kit on the back of the t-case or something at the rear brakes.
I'll be using a fj60 rear axle so I have parking brake option. How much longer is the split case versus the 3 speed? I don't need exact numbers...
 
it will be going on a NV4500. Since I'll be buying an adapter for the transmission anyways

By this statement assume you haven't already purchased the adapter?
I have considered the split case option but all I have been able to find locally are 1k and up then I still need the low range gears which are about 1k and up from my understanding plus rebuild kit, I figure at the end I'd be in it at about 2.5k which isn't terrible if it's truly worth it.

Interesting didn't think split case prices have gotten that ridiculous. Bought one five years ago for $500. It also included the H41 and hand brake.

I'll be using a fj60 rear axle so I have parking brake option. How much longer is the split case versus the 3 speed? I don't need exact numbers...


SOR shows the FJ40 four speed driveshafts being the same 74-84. Would make one piece transfer with the hand brake the same split case without hand brake. One piece cases are the same dimensions for three and speed transmissions. Have have driveshafts from a one piece with hand brake and later split case without hand brake and there are really close. If your adding a NV4500 you need to change driveshaft lengths anyway.
 
All measurements from the t-case mounting surface. For comparison only.
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By this statement assume you haven't already purchased the adapter?


Interesting didn't think split case prices have gotten that ridiculous. Bought one five years ago for $500. It also included the H41 and hand brake.




SOR shows the FJ40 four speed driveshafts being the same 74-84. Would make one piece transfer with the hand brake the same split case without hand brake. One piece cases are the same dimensions for three and speed transmissions. Have have driveshafts from a one piece with hand brake and later split case without hand brake and there are really close. If your adding a NV4500 you need to change driveshaft lengths anyway.
That is correct, I have not bought the adapter just yet which is why I wanted to ask some questions first. I am going to have new driveshafts made so not particularly worried about that.
 
Rear output.
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Dimensionally the split case "case" is larger overall, particularly on the top side off the back of the tranny and presents challenges as you move it rearward, especially with a long combo like a 4L60E. All doable, just takes a little clearance work.
 
That is correct, I have not bought the adapter just yet which is why I wanted to ask some questions first. I am going to have new driveshafts made so not particularly worried about that.

Something to keep in mind is the three speed driveshaft flanges are different the four speed. 8/84 the 60 series driveshaft flange pattern changed again. If you already have a 60 series rear axle (maybe a front axle to match ?) Might find out which pattern it has. Then if you go with a split case try and match flanges. Not a big deal but planning ahead can help with the nickel and dime costs.
 

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