NP205 swap in... need details.

[BizeeB65]

I am swapping in 27 spline NP205 to go behind my TH350 and replace my NP203 this weekend. I need some details for anyone from anyone who has done this on a K5.

I dont have new bolts for the adapter to transmission part of the adapter plate. Will the four old ones from the NP203 plate work (ie, are they long enough?) to bolt the 205 plate to the transmission?

Anyone know the fluid capacity of a NP205? My book doesnt have it. All the manuals and writeups I found in searching doesnt have it.

The female to female coupler I have I bought seperately to join the input shaft on the 205 and my output shaft on the tranny. One end has splines all the way up to the edge, the other end has splines that end about 3/8" from the edge of the coupler. Anyone know which way this goes (which end goes toward the tranny, which end toward the t-case)?

Any and all help is appreciated.

PS - I have searched and read on this stuff for the past 3 weeks since I decided to do the swap, so no flaming for not searchin!

 

[MEK5]

The 203 bolts should work if they are 1 1/4-1 1/2 long.
The 205 holds 2qts. and the side of the coupling that has the recessed splines goes towards the transfer, if you look at the input gear you will see an o-ring that fits in that non splined part.

 

[BizeeB65]

Sweet... now about the fluid. the t-case had atf in it, and i know for sure it was more than two quarts.... almost more like 4 to 5.... should I run that or should I run gear oil?

 

[MEK5]

Sweet... now about the fluid. the t-case had atf in it, and i know for sure it was more than two quarts.... almost more like 4 to 5.... should I run that or should I run gear oil?

In the 80s GM started using ATF in the 205 vs gear oil,my guess would be less drag/better mileage.There is nothing inside that is any different from the early and late cases both still used a combination of roller and needle type bearings.I have not heard about any ill effects from using ATF but personally like gear oil in mine!!!
On a side note most of the threaded holes on a 205 are thru holes and are known to be leakers if everything is not sealed up properly including the bolt threads.

205s hold only 2qts if you drained 4 or 5 qts of ATF from yours I would suggest that you better pick-up a coupling seals for your adapter before you install it

 

[BizeeB65]

Good call.... good call.. I will grab that seal in the morning when I get the tranny jack. I must be a fool to want to lay in the rain tomorrow and do this swap but I am tired of letting it sit around. I'll probably get sick too...

MEK5, your knowledge of the 205 is vast!