so in the 86 k5 i got the guy told me it had a 208 in it. it looks like the tag is ripped off cause there is a clean spot where it belongs. anyways it was probably ran without the front driveshaft for a while so im guessing thats not good. and with the rear shaft it has a lot of play where it mates with the t-case and its leaking what looks like transmission fluid.

does this mean that the transfer case is pretty much shot? if so i had the idea of taking the 203 out of the 74 i have and mating that with the th400 i also have. i think this would be a good setup maybe. i need your guys's opinions. thanks.

 

I'd guess that it's an NP208. Your best bet is to find another NP208 to use. Finding an NP203 to TH400 adapter is just a little easier than finding a NP203 to TH350 adapter which is very difficult. And you would have to see what the input spline count is on the NP203. TH400's have 32 spline output shafts. TH350's have 27 spline output shafts so if your NP203 was originally behind a TH350 (or worse, an SM465 with 9 splines, IIRC), then you'd have to swap the input shaft in the NP203 range box.

Better yet, try to find a passenger drop NP241 (needle meet haystack).

 

HUH??? all i got out of that is that it wont fit.... is that correct? i know that the th400 i have already has an adapter on it. not sure if its for a 208 or a 203 or whatever. im looking to tear apart the th400 and rebuild it or something. it has been sitting for a while without fluid in it so im not sure if its going to have any problems or not. the shafts spin. meaning i can turn them by hand. its hard but i can do it. and the park gear works and so do all the other ones.

but mainly your saying that it wont fit? could i just take the 203 and put it on the th350 that is already in the truck? its already on a th350 right now.

 

nah you cant just go swapping transfercases around. i wish it was that easy. basically pretty much for the 3 cases 203, 205, and 208 all require different output shaft lengths and different adapters. also you cant use one off a th400 as it has a bigger output shaft and more spline counts.

the front driveshaft not being run shouldnt matter at all, also pretty much all slip yolk style transfercases like the 208 have a little bit of up and down play. i have a 208 in two trucks i own and both those rear output leaks no matter how many times i changes the seals. i dont know if its cause they are lifted or what.

but if its not making noise, everything works just run it.

 

alright then. ill just run it till i break it. and i have to get a driveshaft that i have cut. he gave me a new one with the truck along with the old one. the new one has to be cut cause its too long and the older one is too short i think. idk. it gives me a headache thinking about it.

 

perfect, if you have a longer one they can cut it down i ended up doing that with my s10 now. the driveshaft i was using was all bent and tore up from the rocks so i found one i had laying around off a k5 blazer and had it shortened, it was pretty cheap like $70. but if you take it somewhere to have them cut it, make sure you call and find out the proper way to measure it. some places do it differently