NP 205 Question

[BrianDamage]

Hey all...been a while...got a question, hope it's not too dumb.


I got a 1987 K5. 700R4 crapped out on me a good while back, and I had a 14bff and dana 60 sitting around, so I went ahead and swapped the axles out.

This summer I bought a used turbo 400 mated to a np205 case. The 205 is the type with the slip-yoke rear output on it.

I ordered a 4inch lift and rear shackle flip from offroad design the other day, and Steve (I think that was his name ) recommended that I lose the slip-yoke rear output for the more common variety. It is the round bolt pattern, not the figure 8 type

Just so happens my father-in-law has 2 abandoned K5's on his farm. One is a 71 GMC and the other a Chevy about the same year... The Chevy has a manual with np205, and the GMC has auto (turbo 350) with np205

we pulled the GMC in the shop today to start tearing it down. my original intention was to use the rear output shaft from the manual 205 and leave the other in tact....but it's in my best interest I think to lay claim to the turbo350/205 combo.

I'm thinking if I'm going to have to buy a rebuild kit to swap the rear output shafts, why not just rebuild the one that already has everything in it already?

So I guess my question is, would it be economically a good idea to do this? I'm going to need another adapter to mate to 205 to the th400 aren't I? Guessing the th350 adapter won't work....am I going to have to change anything on the TH400 shaft wise, since it is already mated to a 205?


Can I take the 205 input shaft from the 205 already mated to the 400, and swap it with the one mated to the th350, and use the adapter from the th350 with the th400/205 combo?
What would yall do?

 

[4X4HIGH]

If you're going to keep the 400/205 combo then you'll still be using the same adapter that is between the 400/205 currently. The 350/205 has a 27 spline input which uses a smaller input bearing than the 32 spline input of the 400 so in order for you to rebuild the 350/205 you would need to bore the case for the larger input bearing and then when you start to build that case you'll need to use your existing 32 spline input gear and bearing.

If you just want to eliminate the slip yoke on your current 205 it is a direct swap of parts from either of the two cases you have access to. Alot less work to just swap the rear outputs than to build another case. I've "built" a bunch of 205's and have never found anything bad in them other than an occasional shift fork having some wear.

 

[Hogback Fabrication]

Can I take the 205 input shaft from the 205 already mated to the 400, and swap it with the one mated to the th350, and use the adapter from the th350 with the th400/205 combo?
What would yall do?

Old 465/205 is 10 spline with a small input bearing in the 205
350/205 is 27 spline with a small input bearing in the 205
400/205 is 32 spline with a big input bearing in the 205

Each one uses its own adapter, they're all different.


Your best bet is to just replace the slip yoke parts in the TH400/205 combo. You can used the fixed yoke parts from any 205.