Hey guys. I have an 81 K5 w/ an NP208 currently. I have already cracked the tailshaft housing, replaced, and the new one has hairline cracks in it and is leaking. I'm over the aluminum case and unrelated, the slip yolk. I picked up a full drivetrain setup over the weekend for what I consider is a good deal. A th350 (mine I think is beginning to slip), and NP203 with rear dirveshaft. So, assuming somehow that I can muscle this thing in there, are there any other issues I'm going to run into. I know that I will probably need to have the 203 driveshaft length modified. What about the front drive shaft? I didn't get the 203 front one so I hope the 208 will bolt up. Also, what about just the basics of mounting it up there? Are there any differences? I'm not wanting to do a doubler as this is a highway/mud truck. No rock crawling here. I have no idea if it is a full time or part time 4wd. Any way to tell? Yes I have alot of questions. I kinda went into this without doing my homework.

 

cross member is different, front and rear driveshaft is different shifter is different, drive shaft lengths will be different, adapter between transfer case to transmission is different.

also the 203 is a fulltime 4x4 case so youre going to have to leave your front end locked in all the time or you arent going anywhere unless its been converted to part time.

you said you got a th350 with it? cause if you try to put the 203 on the back of your th350 it wont fit, the output shaft is going to be to long.

i personally hate the 203, that big awkward turd is a **** to get get in and out of the truck if you ever have to mess with it. usually people up grade to the 205 due to it being gear driven, smaller, cast iron and a part time case.

but on the other hand i wheeled a 203 for a few years and have never broke anything on it, it just leaked out of everything. and it takes motor oil