400 Turbo 2WD to 4WD question

[Patriot]

Hello again fellas, I need to pick your brains again. I just parted out my 78 2WD Suburban 454/400 Turbo truck and was wondering if that 400 turbo can be used in a 4WD application. Has anyone done this here?? I have a 79 K5 Blazer that I want to put the 400 Turbo in and get rid of the 350 Turbo 203 combo. I WANT to install the 454 also. I just want to make it look totally factory even though they didn't come with 454s. Thanks again fellas, this absolutely the best site on the internet. You guys are a class act.




Patriot

[andrewmp6]

I know it can be done i think it just takes changing the tail end to a 4wd one but i would let a shop do it if it was me.

[donut]

It can be done, but not just a bolt in deal. IMO, the easiest way is find a complete 4x4 driveline and use that. (or build up the th350, how long it lasts behind a 454 is up to you.)

The output shafts are different from 2wd to 4wd and the inputs on the transfer case are different from the th350>400. (which means the transfer case adapter is also different.) Not 100% sure, but I believe overall length may be different, which may require some driveshaft work. (lengthen front shaft, shorten rear?)

[ghettoluxury]

A 2wd TH400 is the perfect tranny for a NP205. If you use a 400/205 adapter the tail shaft between the 2wd and 4wd is 1/4" difference. A 32 splines 205 with a 400 adapter will bolt right up.