TH400 swap

[browny]

nowdays i'm working on my 1977 k5 blazer

it has a manual trans with NP205 , my qustion is can i swap my manual trans into TH400 , what i need to do to swap it ?

 

[sweetk30]

nope not a direct swap.

you need a th400 with a 205 on it.

the 465/205 you have now has a 10 spline output/input gear from 1 to the other.

the th400 has a 32 spline output shaft so you need a 205 with the 32 spline input gear on it. but watch out there is a few diffrent length inputs for the 205 short input takes a figure 8 pattern adaptor on the tcase side ( like yours now on the 465/205 ) and the long input takes a round 6 pattern adaptor to the tcase face. this inturn makes for 2 diffrent length output shafts on the th400.

also you need the gas pedel bracket and switch with wiring for the th400 to kick down in passing gear .

also you will need diffrent length drive shafts as the th400/205 is diffrent overall length than the 465/205 you have now.

this will get you started on the correct road for now. search button here will get you tons of info on these trucks.

 

[76zimmer]

Crossmember?
Trans lines to the radiator for the cooler...don't run just an auxillary cooler, unless its a summer time only rig.
Shifter...I'd go ArtCarr/Winters, otherwise you'll need to change steering columns for the on the tree shifter.
Flywheel, torque convertor, inspection cover.
Modulator line to the intake manifold.
Speedo cable change????
Be aware the trans case cannot take twisting forces that the iron case 4 speed could, mount it accordingly...see the mother of all double thread for some ideas if you do anything other than factory.

 

[phreddei166]

I did the 465/205 to 400/205 swap 2 years ago. Best thing I ever did to it. PM me if you have questions. Best advice....... Don't use B&M Truck Megashifter. Its a pile of .

 

[sweetk30]

Don't use B&M Truck Megashifter. Its a pile of .

x2 hated mine from years ago.

so when i went from 465/205 to a 400/205 i did some lookin and found a sweet shifter from lokar.

get the 23" double bend in midnight series black for stock 4 speed look. and here is cheepest place i found recently. http://www.rjays.com/Lokar/lok-nos-shifters-01.htm

thay also offer shift button upgrade for only $19.95 swapout of stock for 3 diffrent choices. i got the pistion knob and love it.

even fit right up threw the 4 speed shifter hole and reinstalled the boot just like 4 speed . fools LOTS of people all the time till thay see only 2 pedals on the floor.