Author Topic: NEED ADVICE -1976 K10 / TH350 TRANSMISSION REPLACEMENT  (Read 7189 times)

Offline jfkelley

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Re: NEED ADVICE -1976 K10 / TH350 TRANSMISSION REPLACEMENT
« Reply #45 on: April 13, 2019, 08:13:06 PM »
Any idea to find an adapter to make that transmission work with my Transfer case ? The mechanic says he puts on the Transfer case adapter from the previous transmission the shafts not long enough ..What if I take that Adapter and have it Milled Down to where I need it to make it work ?



Any idea to find an adapter to make that transmission work with my Transfer case ? The mechanic says he puts on the Transfer case adapter from the previous transmission the shafts not long enough ..What if I take that Adapter and have it Milled Down to where I need it to make it work ?
1976 Chevrolet Scottsdale 4x4 ,K10 33” BF Goodrich All-Terrain .. in the middle of an LS swap LM7/4l60e/NP241C

Offline Irish_Alley

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Re: NEED ADVICE -1976 K10 / TH350 TRANSMISSION REPLACEMENT
« Reply #46 on: April 13, 2019, 08:41:44 PM »
im kind of in unknown territory right now so i cant really say what will work or not. so the mechanic put the old adapter on and the outputshaft is too short?. doesnt make sense.
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline JohnnyPopper

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Re: NEED ADVICE -1976 K10 / TH350 TRANSMISSION REPLACEMENT
« Reply #47 on: April 13, 2019, 09:27:21 PM »
First, your shop is incompetent, look for someone else if you can find them. Don't pay them a dime, they are liars!

Second, the problem you're having is the output shaft is not the right length. Don't spend anymore energy on it.

Get your original rebuilt and sell the other.

Done and done!

"the world is full of imposters" T. Khoury.
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline jfkelley

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Re: NEED ADVICE -1976 K10 / TH350 TRANSMISSION REPLACEMENT
« Reply #48 on: April 13, 2019, 10:05:45 PM »
First, your shop is incompetent, look for someone else if you can find them. Don't pay them a dime, they are liars!

Second, the problem you're having is the output shaft is not the right length. Don't spend anymore energy on it.

Get your original rebuilt and sell the other.

Done and done!

"the world is full of imposters" T. Khoury.


I was starting to wonder if they knew what they were doing after the 1st week ...They already have the Transmission installed and I paid 1//2 down ...I feel so embarrassed because i thought it would be a easy replacement
1976 Chevrolet Scottsdale 4x4 ,K10 33” BF Goodrich All-Terrain .. in the middle of an LS swap LM7/4l60e/NP241C

Offline Irish_Alley

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Re: NEED ADVICE -1976 K10 / TH350 TRANSMISSION REPLACEMENT
« Reply #49 on: April 14, 2019, 08:13:46 AM »
im with johnny, either rebuild your old th350 OR replace it with a 700r4 (for the OD)
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline JohnnyPopper

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Re: NEED ADVICE -1976 K10 / TH350 TRANSMISSION REPLACEMENT
« Reply #50 on: April 14, 2019, 05:13:08 PM »
Well, you can make lemonade from lemons...

If I were in your shoes I would try this:

(And this is on the assumption that you are dealing with a transmission rebuild outfit)

Gut your original TH350, and transplant the good parts of your replacement transmission into your original housing.

You will need to use the original output shaft, as that matches your transfer case.

If they are not a transmission outfit, have them take out the transmission and find a shop that can do the work I listed above.

Mr. Kelly, in either case, you have the  wrong transmission in your truck at the moment. These guys should have spotted it right away.
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline Irish_Alley

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Re: NEED ADVICE -1976 K10 / TH350 TRANSMISSION REPLACEMENT
« Reply #51 on: April 19, 2019, 03:33:46 PM »
10-30w or SAE30 Non-Detergent for the 203
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes