Author Topic: What transmission do I need?  (Read 75 times)

Offline Rough75C20

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What transmission do I need?
« on: November 04, 2025, 04:56:57 pm »
Hello,

I’m waiting on a transmission to be rebuilt, but can no longer wait as the place I’m storing it needs it moved. I don’t have the transmission and the guy rebuilding it won’t contact me. The guy probably stole it. Either way, I need to figure out how to know what th350 I need. Are there different versions? I have the two piece driveshaft and it is a 2wd long bed with a 305 engine. How do I tell?

Thank you


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« Last Edit: November 04, 2025, 05:05:14 pm by Rough75C20 »

Offline zieg85

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Re: What transmission do I need?
« Reply #1 on: November 04, 2025, 06:13:25 pm »
TH350 with a 9" tail shaft should have been in there if it was always an automatic.
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
https://www.facebook.com/groups/248658382003506/

Offline Rough75C20

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Re: What transmission do I need?
« Reply #2 on: November 04, 2025, 06:24:45 pm »
TH350 with a 9" tail shaft should have been in there if it was always an automatic.
Awesome. I’ll look for that. Anything else that I need to look for other than the 9 inch tail shaft to make sure it will work with the driveshaft?

Offline zieg85

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Re: What transmission do I need?
« Reply #3 on: November 04, 2025, 07:08:10 pm »
Output shafts are all the same spline in the TH350 and TH350C.  A 700R4 swaps in if you move the cross member a little.  Attached is measurements
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
https://www.facebook.com/groups/248658382003506/