Transfercase as a low range box

[Okiefromwatonga]

I was just wondering if anyone has used a Transfercase as a low range box in a 2 wheel drive rig and went with more highway friendly gearing in the rear end?
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[kwmech]

Something like this

[kwmech]

I built this to fit behind an SM465. Makes it nice for backing up a 35' goose without riding the clutch all the time

[Okiefromwatonga]

That's exactly what I'm talking about. How well does it work for you?
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[franken]

That looks like an NP203 range box that gives a 2:1 underdrive. You can also get range boxes that use planetary gears from various newer (NP241 at 2.6:1 for example) TCs. Of course, they're generally made to bolt to a 4x4 trans and a TC so some adapting would be needed.

[Okiefromwatonga]

Originally Posted by franken

That looks like an NP203 range box that gives a 2:1 underdrive. You can also get range boxes that use planetary gears from various newer (NP241 at 2.6:1 for example) TCs. Of course, they're generally made to bolt to a 4x4 trans and a TC so some adapting would be needed.

That's why I ask as the trucks I am looking at that could be donors most are 4x4's and have married xfer cases

[C10 - C90 Bill]

I always wanted to try that myself. I really don't know why it isn't more popular than it is out there. I was talking to a friend of mine, who was quite the mechanic, and he told me that he installed one in one of his pick-ups. Although I never got to see the truck, he said it worked great.

[sweetk30]

if your transfer case has 2 shift rails 1 for front in/out and other for range high/low its easy to twin stick them for this .

like a np205 can be twin sticked for 2wd rear high-n-low and front wheel drive high-n-low if the shift rail is modified .

even a stock np203 full time with conversion kit can be twin sticked . the same as above but just a bolt on shifter kit .

i twin stik my 205 t-cases and they shift better and yes the 2wd low is super nice for slow easy work .

offroad design way back in the day had a kit for the rear of a 203 range box to make it have a rear output yoke . but it didnt take off sale wise . . . .and the 2 pics above even look like a offroad design cut plate for the rear .

ford used a divorced np203 full time for a few years . so it could be made to work easyish if you could make the back half kit like the pics above .

[kwmech]

The pic above is my own design with the only the aluminum plate from North West Fab. I had the 203 original shaft cut and resplined to the 465 output splines (35 I think) and the hole drilled and threaded for the retaining bolt. I then took the back from the 465 for the bearing retainer and speedo hook up, transferred the mounting bolt to the aluminum....drilled and tapped them. The bolt and washer in the center of the yoke is from a BB chevy. Made a gasket and built the unit. With the correct adapter, this will bolt up to a turbo 400 also.....or if you swap the input to 27 spline it will bolt to a t350 also