71FJ Low Gear options (1 Viewer)

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I need a little advice. I have a 71FJ40 with 350 engine turbo 400 trans twin stick 3 speed transfer case. I am wanting lower gears for crawling. I have been doing research and wanted different opinions. Advanced Adapters offer a doubler kit to couple a NP205 to my 3 speed LC case. Pretty reasonably prices.

They also offer the Orion that is around $1,500 befor shipping. Its double the price but upgrades to a stronger case, and I wont have to mess with drive shaft lenghts again,

Are there any other options or are these the only two I have. Thanks for all of your input.
 
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The TH-400 is pretty long to begin with. Running a np203 doubler with your stock t-case is going to make things even longer (figure in new driveshafts, perhaps even moving your axle back)

With an Orion it will bolt in.
It' will bolt up directly to the adapter you already have.
Your driveshafts will bolt up directly to the Orion.

Another option would be to swap in an SM420 or a 465 with the stock 3 speed t-case. But then again your going to have to get the SM4xx, the necessary bellhousing and clutch parts. new driveshafts etc.

A third option would be to run a toy box, but then youa re running into the same problems as the NP203.

When you start putting stuff down on paper, when it's all said and done, the orion is going to be the best bang for the buck for what you've already got.
 
Be aware the Orion 4:1 gears are kind of slow for most trails.
Unless you do mostly crawling you might be unhappy.

But I love my Orion.
 
I am leaning towards the Orion. I see they have it in a 3:1 or a 4:1. Anyone have the 3:1 out there? I forgot to mention my cruiser already has the rear springs flipped and a SOA lift. I just dont know if I want to mess with the doubler. Seems like Orion is the way to go. Thanks again.
 
One more thing.
I am looking at AA and Novaks web sites.
Neither of them seem to make a TH400 to NP203 adapter (might be a factory GM Piece?).
But for a ball park figure, $500 for the NP203 to 3 speed case adapter. Anther 490 for the TH400-NP203 adapter (assuming it costs what an MP205 adapter costs) your lookign at almost $1000. Then ya gotta buy tghe NP203. Rebuild the GRB. Then drive shafts.. Etc. You're looking at more than what the Orion costs and what someone else said it probably won't fit.

In your situation, I'd look at the Orion 3:1 bolt it up and have FUN.
 
I need a little advice. I have a 71FJ40 with 350 engine turbo 400 trans twin stick 3 speed transfer case. I am wanting lower gears for crawling.




Welcome.



What size tires are you currently running, and where do you see the truck/what size tires do you see on it in three-plus years?
 
Hi All:

First off, I don't know much about auto trannies, but would changing the torque converter and/or stall ratio of this TH400 help "slow-down" the rig on the trails?

Regards,

Alan
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I need a little advice. I have a 71FJ40 with 350 engine turbo 400 trans twin stick 3 speed transfer case. I am wanting lower gears for crawling. I have been doing research and wanted different opinions.
 

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