Author Topic: th350 to th400 swap/whodunit?  (Read 5565 times)

Offline 07montecarlo

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th350 to th400 swap/whodunit?
« on: February 08, 2010, 06:28:37 AM »
what do i need to accomplish the swap.. now is a long shaft 350 the 400 is short, im sure ill need new yolk/driveline. what about mounting? will the 400 fit the tunnel? crossmember bolt up or do i need to drill holes??

Offline Captkaos

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Re: th350 to th400 swap/whodunit?
« Reply #1 on: February 08, 2010, 03:44:48 PM »
What year?  4x4 or 4x2?  The Trans crossmember just needs to be moved back to the TH350 location.

Offline VileZambonie

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Re: th350 to th400 swap/whodunit?
« Reply #2 on: February 08, 2010, 03:51:54 PM »
You'll need the detent switch and wiring... Other than the driveshaft the rest is pretty straight forward.
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Offline 07montecarlo

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Re: th350 to th400 swap/whodunit?
« Reply #3 on: February 08, 2010, 05:57:33 PM »
manual valve body no detent wanted.. and did you mean move to th400 holes?? and can i still use a single driveline??

sorry 2 wheel drive street truck

Offline Captkaos

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Re: th350 to th400 swap/whodunit?
« Reply #4 on: February 08, 2010, 09:14:23 PM »
yeah, sorry.  To the set of holes for the TH400.  Read that backwards.

Offline 07montecarlo

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Re: th350 to th400 swap/whodunit?
« Reply #5 on: February 09, 2010, 02:53:14 PM »
yeah, sorry.  To the set of holes for the TH400.  Read that backwards.

what about driveline, just make it longer or do i need slip type?

Offline Captkaos

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Re: th350 to th400 swap/whodunit?
« Reply #6 on: February 10, 2010, 12:12:00 AM »
Should be shorter going to a TH400

Offline 07montecarlo

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Re: th350 to th400 swap/whodunit?
« Reply #7 on: February 10, 2010, 05:28:35 AM »
the 350 in the truck now is long shaft and the 400 is short shaft.. will i still need shorter driveline? rather have shorter than longer thats for sure

Offline VileZambonie

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Re: th350 to th400 swap/whodunit?
« Reply #8 on: February 10, 2010, 06:33:10 AM »
I'm not sure what you're asking? If you have a short shaft Th-400 you'll need a different driveshaft. The yoke on the 400 you have is bolted to the tail shaft right? You'll need a drive shaft like this one in this thread http://forum.73-87chevytrucks.com/smforum/index.php?topic=7334.60
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Offline 07montecarlo

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Re: th350 to th400 swap/whodunit?
« Reply #9 on: February 12, 2010, 06:20:02 AM »
yolk is not bolted to tailshaft.. i just have a stock th350 long tail with one piece driveline going to truck 12 bolt.. the th400 going in is short shaft.. will i need to have a driveshaft built??