Transfer Cases and where to find them..

[SnowGecko]

OK, most or just about 99.99% of everyone goes with the 'part time' or some kind of 'converted' part time... but this time... I'm the 00.01% that isn't.


I'm looking for a NP119 or NP129 or a NP147

IDK where to find them, which vehicles have them, OR if they bolt up to the 700r4.

plan... Street driven 4wd... with no center shifter.

I can go a NP203 or something similar.. but don't want the 'extra' if it's never going to be used.

https://en.wikipedia.org/wiki/New_Venture_Gear

going off this 'wiki' link... the viscous NP119 and NP129 would be great. IMO. it's single speed, the 129 has a 2wd mode, probably electronic. but I don't have to hook that up, I hope.

I need it to bolt to the planned 700r4.

any help would be appreciated.

[andrewmp6]

It will help to know what truck its going in because not all years used the same side drop t case.

['63GENIII]

2004 Yukon Denali XL. 6.0 liter NVG 149. Drivers side drop and mated to a 4L65E.

Theres probably others too. Just what we have. No extra shifter. Viscous clutch.

[SnowGecko]

This is going in a first Gen longhorn, 1972 chevy, it has the 402 and I'm adding a 700r4 transmission.

I believe I'll need passenger side drop right?

[andrewmp6]

Yes you need passenger side drop,The problem is most new gm trucks are driver side drop now so all those awd t cases won't work.With a 700r4 your t case options are limited with out running a adapter kit,Stock you got a np208 and a np241.Or swap in a ford front axle which is drivers side drop but that can be a big job to do right.

[SnowGecko]

in general, If i did open the option for any trans, but kept the 402bb engine, what can I come up with that will bolt in?

4L80e option? with which case?
any other trans that I can use? that will hold up to the power of the 402


I don't think I'm skilled or padded enough for the ford axle route...

[andrewmp6]

Stock trans you could do a turbo 400/np203 or np205 and use a gear vendors overdrive for the overdrive.To use a 4l80e you probably need a adapter kit to use it on your engine,And then the t case will take a adapter kit also since its a newer trans and the stock t cases on them are the wrong drop.But most of the t case adapter kits use on a 2wd trans which will take a trans shop to do but a 2wd trans is a lot cheaper and easier to find then a 4x4 one.And youll need a controler for a modern trans.I would look in to a beefed up 700r4 and run a late 80s np241 which both should handle the power unless you want some extreme 4x4 out of the truck.

[bilfman]

4l80e will bolt right up to a big block. Basically the same case as a th400. You will need an after market controller. I use the TCI unit, super easy to install and has worked flawlessly for years, even in our awful Canadian winters. I am very happy with my BBC and 4l80e.

[andrewmp6]

If you get super lucky the 91 crew cab old body style aka square body,Had the 4l80e np204 combo for one year and its a passenger side drop.Bilfman has that combo from that truck he can help you with the swap.

[SnowGecko]

so for 'simplicity sake'...


402 + 4l80e (tci unit) + np203 should bolt up...


is there any reason to go 4l80e over the 700r4? is it really the bolt on for the transfer case?

Can I safely keep the NP203 in 'full time 4wd' and not install a shifter?

is there a single 'cable' shifter for the NP203? so it can be moved away from the bench seat.

[andrewmp6]

I have no clue if that np203 will bolt on it or not.They have a few different bolt patterns for the t cases and the output shaft theres 3 different splines and the length is different on them.Worse case maybe a adapter kit but im not sure.I would talk to http://offroaddesign.com/ they do stuff like this a lot they might have better answers on using that t case.

[andrewmp6]

Or another option http://www.gearvendors.com/index.html that bolts on to the end of your t case and gives you a over drive gear on a trans that didn't have it.

[SnowGecko]

gear Vendors is not an option.


from a 700r4 to a NP203
http://www.advanceadapters.com/produ...placing-th400/

[andrewmp6]

You use to use that kit you have to take the trans almost fully parts to replace the output shaft,So keep that in mind and budget and if it was me id have a trans shop rebuild it and beef it up to handle the power you have.And you will have to replace both driveshafts since the over drive trans is longer then yours keep that in mind.You might get lucky and get a used from one off a later truck but the rear im not sure if you can find one the right size or not.Worse case i have had driveshafts made locally for 350 each at a big diesel repair shop.