Need help with a trans swap

[Freddyj323]

Alright, my name is Josh and i bought my first 69 chevy c10 pickup about three days ago. It was originally a 307/ 3 speed manual but the guy put in a 327 instead. Its the hugger orange with white top. Only rust is on the drivers side rocker and i already got it fixed. Now the big question, I really want to swap out the 3 speed for an automatic. Im told a TH350 would probably be the easiest but i do have a brand new TH400 sitting out in the garage. Now i am wondering what adjustments i am gonna have to do.... shortening the driveshaft...get a new driveshaft.....will it bolt up to the engine....moving the cross member....something about a pilot bearing??? Help?

Thanks
josh

[72cheysuper]

Hey Josh,
The 400 turbo will work just as nicely as the 350 turbo. There is a bearing in the end of the crankshaft of your engine which is to support the shaft of your standard transmission. You will only need to pry it out. The shaft on the auto transmission will rest in the torque converter, so the bearing wont be needed. Dont know if you thought about it but, you will need the torque converter and flexplate for the automatic. And, you'll need the automatic steering column and shift linkage unless you plan to install a floor shifter. Depending on which cross member and drive shaft you currently have under your truck, you may have to simply swap them for the correct ones out of an automatic truck. You'll also be needing an automatic radiator and lines. Dont forget to run a vacumm line down to the modulator valve. Hope this helps.

[Jtrux]

The pilot bearing can stay, it won't be in the way. You really don't have to change the radiator, you can opt for simply putting an aftermarket tranny cooler in front of the radiator if your radiator is in good shape. Your TH400 has a lower first gear so depending on what you do it might work out better for you or you might not even be able to tell since your going from the 3 speed.
Edited by mod. No selling of parts on this part of the board, nor by nonsubscribed members.

[Freddyj323]

alright guys thanks...ya im puttin in a 383 that was in my auto chevelle so i got a 2500 stall converter and flexplate...my big issue is the driveshaft, im really hopin i dont have to cut it or get a new yoke.. does anyone know if the yoke for a th350 and 3 speed are the same..i know a th400 is different than anything else but i dont know?
thanks for the help

[berencam]

save that 327 its worth some moolah

[michael bustamante]

Originally Posted by Freddyj323

alright guys thanks...ya im puttin in a 383 that was in my auto chevelle so i got a 2500 stall converter and flexplate...my big issue is the driveshaft, im really hopin i dont have to cut it or get a new yoke.. does anyone know if the yoke for a th350 and 3 speed are the same..i know a th400 is different than anything else but i dont know?
thanks for the help

if I remember correctly, the splines are different. youll have to replace the yokes, also dont forget the kickdown cable and linkage/mounting brackets. minesa long bed, 2 piece driveline and I did have to get my line shortened a little, I have the long turbo 350. I dont know about shortening with the 400 trans

[Slammed70]

Post some pics or your an RMT...

And welcome from Cheney, Kansas.