TH350 adapter question

[jekquistk5]

I picked up a new(used) th350 and it was supposed to have a 205 attached to it but it ended up being a 203. I have a bad TH350 attached to a 208 in my truck now. It has a spacer block between the NP208 adapter and the end of the trans. I assume that is because it has a longer tailshaft. The trans I picked up does not have this block and the tailshaft sits almost even with the end of the trans. My question is can I use my 208 just take out the spacer, and use the adapter from the 208? I am also assuming that the spline count is the same. Or do I have to swap tailshafts? Just starting to get my ducks in a row before i go tearing into everything.

 

[chevyuser74]

im pretty sure the tailshaft is different, but someone should tune in soon

 

[4X4HIGH]

I picked up a new(used) th350 and it was supposed to have a 205 attached to it but it ended up being a 203. I have a bad TH350 attached to a 208 in my truck now. It has a spacer block between the NP208 adapter and the end of the trans. I assume that is because it has a longer tailshaft. The trans I picked up does not have this block and the tailshaft sits almost even with the end of the trans. My question is can I use my 208 just take out the spacer, and use the adapter from the 208? I am also assuming that the spline count is the same. Or do I have to swap tailshafts? Just starting to get my ducks in a row before i go tearing into everything.

Sounds like your bad TH350 has the teckpak fitzall kit in it that allows the use of a TH350 in place of a 700R4. You would need to replace the tailshaft in order to use the (new) TH350 with your 208.

 

[imiceman44]

I picked up a new(used) th350 and it was supposed to have a 205 attached to it but it ended up being a 203. I have a bad TH350 attached to a 208 in my truck now. It has a spacer block between the NP208 adapter and the end of the trans. I assume that is because it has a longer tailshaft. The trans I picked up does not have this block and the tailshaft sits almost even with the end of the trans. My question is can I use my 208 just take out the spacer, and use the adapter from the 208? I am also assuming that the spline count is the same. Or do I have to swap tailshafts? Just starting to get my ducks in a row before i go tearing into everything.

If you want to find a tranny that easier to mate to your 208 a 700R4 4wd would fit better.
The th350 you got now with the short shaft will only fit a 203 like what is on it or a 205 27 spline which uses a female coupler that connect the short shafts together.
Your 208 is female already and was available one year 81 behind the th350 then they came with the 700R4 in 82
You could swap the shaft you have to the new th350 but then you could rebuild yours if you are going to do that.
Why not use the 203 that comes with the th350, until you find a better option.

 

[jekquistk5]

If you want to find a tranny that easier to mate to your 208 a 700R4 4wd would fit better.
The th350 you got now with the short shaft will only fit a 203 like what is on it or a 205 27 spline which uses a female coupler that connect the short shafts together.
Your 208 is female already and was available one year 81 behind the th350 then they came with the 700R4 in 82
You could swap the shaft you have to the new th350 but then you could rebuild yours if you are going to do that.
Why not use the 203 that comes with the th350, until you find a better option.

Thinking about it, but I would have to get the part time conversion first, I do a lot of 2wd running in the sand dunes, and other places.