Can't seem to find the right answer for this. I have an 86' K30 1 ton with the factory TH400 and 205 case. I have a 203 from a mid 70's GM. What parts do I need to get these running together. I have read anything from some thick adapters to input/out put shafts and I'm very confused.
CK5
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TH400 to 203/205 doubler help
- Thread starter sw99
- Start date
if remaning th400 swap in 203 specific tail shaft and correct adaptor to 203 for the 400 .
is your 203 from a th400 with 32 spline input gear ? if not going to need a new one or good used and swap that over.
but if you got time and dont mind little checking and making what ya got work do like i did .
i used a 4l80-e tranny with 4l80-e to 241 adaptor . tranny was swaped to full spline 2wd tail shaft and extra cut off.
then new tcase adaptor pattern drilled / tapped in the 203 range box .
here is my build thread for some help . http://coloradok5.com/forums/showthread.php?t=253000
and here is the 400 tranny tail shafts ( pic ) 86 th400 will have bottom row shaft 2 long input style. you might be able to cut off the extra to make it a 203 shaft and work for you .
also tons of info in here . and great kit for doublers and any parts you will need. http://offroaddesign.com/catalog/doubler.htm
fill in these questions and we can go from there.
is your 203 from a th400 with 32 spline input gear ? if not going to need a new one or good used and swap that over.
but if you got time and dont mind little checking and making what ya got work do like i did .
i used a 4l80-e tranny with 4l80-e to 241 adaptor . tranny was swaped to full spline 2wd tail shaft and extra cut off.
then new tcase adaptor pattern drilled / tapped in the 203 range box .
here is my build thread for some help . http://coloradok5.com/forums/showthread.php?t=253000
and here is the 400 tranny tail shafts ( pic ) 86 th400 will have bottom row shaft 2 long input style. you might be able to cut off the extra to make it a 203 shaft and work for you .
also tons of info in here . and great kit for doublers and any parts you will need. http://offroaddesign.com/catalog/doubler.htm
fill in these questions and we can go from there.
i would check and see if your tail shaft now is full spline like pic i posted.
if so cut it down so you dont ned to tear down the whole tranny for tail shaft swap .
then you need adaptor for th400-203 tcase.
then you need a doubler kit from ord / or few others.
last read threw my build so you can do it all your self easy .
if so cut it down so you dont ned to tear down the whole tranny for tail shaft swap .
then you need adaptor for th400-203 tcase.
then you need a doubler kit from ord / or few others.
last read threw my build so you can do it all your self easy .
i would check and see if your tail shaft now is full spline like pic i posted.
if so cut it down so you dont ned to tear down the whole tranny for tail shaft swap .
then you need adaptor for th400-203 tcase.
then you need a doubler kit from ord / or few others.
last read threw my build so you can do it all your self easy .
DO THIS! It will save you some headaches, I went through the same thing!
Sound like that will be my first to do on this. What are the chances I have a shaft that I will be able to cut down? From what I keep reading it should be the longer shaft but it doesn't look long enough to cut down and still be able to use.
RE READ MY POST WITH THE TRANNY SHAFT PIC AND READ THE PIC INFO 
