The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 06-12-2008, 03:17 PM   #1
Freddyj323
Registered User
 
Join Date: Jun 2008
Location: Kansas
Posts: 4
Need help with a trans swap

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
Freddyj323 is offline   Reply With Quote
Old 06-12-2008, 05:54 PM   #2
72cheysuper
Registered User
 
72cheysuper's Avatar
 
Join Date: May 2008
Location: Parkersburg WV
Posts: 26
Re: Need help with a trans swap

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.
72cheysuper is offline   Reply With Quote
Old 06-12-2008, 05:59 PM   #3
Jtrux
I'm a poor spectator
 
Jtrux's Avatar
 
Join Date: Aug 2006
Location: San Antonio, Tx
Posts: 2,287
Re: Need help with a trans swap

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.
__________________
2006 Jeep Unlimited IMPACT ORANGE

1993 Chevy 2500 4x4 ExCab LWB 454/NV4500 Tow rig

1977 Ford F100 2x4 LWB 1st truck I owned, still have it!!!

1979 Ford F150 4x4 SWB Built Ford Tough!!!

1971 Chevy Blazer 350 / SM465 / NP205 UNDER CONSTRUCTION Soon to have a LQ4 6.0!!!

Last edited by Longhorn Man; 06-12-2008 at 08:24 PM.
Jtrux is offline   Reply With Quote
Old 06-13-2008, 11:33 AM   #4
Freddyj323
Registered User
 
Join Date: Jun 2008
Location: Kansas
Posts: 4
Re: Need help with a trans swap

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
Freddyj323 is offline   Reply With Quote
Old 06-13-2008, 11:52 AM   #5
berencam
Registered User
 
berencam's Avatar
 
Join Date: Aug 2007
Location: branson mo
Posts: 933
Re: Need help with a trans swap

save that 327 its worth some moolah
__________________
69 chevy c10 350 3 speed manual wood bed build thread here r.i.p.
70 c10 auto 350 build here
berencam is offline   Reply With Quote
Old 06-13-2008, 12:10 PM   #6
michael bustamante
Senior Member
 
michael bustamante's Avatar
 
Join Date: Sep 2007
Location: Albuquerque NM
Posts: 7,855
Re: Need help with a trans swap

Quote:
Originally Posted by Freddyj323 View Post
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
__________________
1967custom
michael bustamante is offline   Reply With Quote
Old 06-13-2008, 12:32 PM   #7
Slammed70
Registered User
 
Slammed70's Avatar
 
Join Date: Oct 2006
Location: Cheney, KS
Posts: 669
Re: Need help with a trans swap

Post some pics or your an RMT...

And welcome from Cheney, Kansas.
__________________
Quote:
ultra rare corvette option package
Slammed70 is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 11:51 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com