Transmission swap

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kevin7035

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I recently purchased my son a 83' Scottsdale 4X4, with 350 4 bolt main and 4 speed with granny gear. He is only 14 and I am teaching him about vehicles and hard work, as he is doing the restoration work himself.

He is wanting to swap the manual transmission for an automatic. We have the engine out now and are doing a mild rebuild on it (325 hp). If I'm going to swap the transmission, now is the time to do it.

My question is, what automatic transmission do I need to look for that will bolt up the 350 sb and accept the transfer case, with minimal modifications. We plan to lift the truck 6" and run 35" tires.
 

MadOgre

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A TH400 but you will need to find the TH400 4x4 adapter for the TH400. The 4spd manual adapter can not be used.

If you wanna get a little crazy you could put a 4L80e in but it would require some modifications!
 

marks86

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sounds like a th400 is the way to go
 

Don5

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You might want to rethink the auto trans version for the truck. Here are just a few reasons for my argument to keep the standard transmission.

1. The standard transmission is very forgiving if you need to work on the engine, front end ,rear end etc. What I mean is that there is nothing to go wrong if the truck sits for any length of time. No bands to loosen up.

2. It will make him a better driver if he learns to drive a standard transmission. It will improve his coordination. This combo is the perfect choice to learn how to drive a standard transmission.

3. You can put whatever camshaft in the engine you want without worrying about having enough vacuum to operate the brakes.

4. Here is the number one reason really to keep the standard transmission in the truck. He will not be able to text and drive at the same time. Trust me he will be too busy driving to do any of that nonsense.

5. He will pay a lot more attention to traffic when he is stopped especially people that pull up right behind him on his bumper. It will force him to become a better driver because he won't pull up right behind someone. No tailgating from him probably for the rest of his life.

I am sure that I can find some more reasons but that is just the few I could come up with.

BTW-I started with a auto trans in my 79, lifted my truck 6 inches and put 36's on it. I promptly went to the 4 speed with a 205 transfer case and then put different front and rear ends under it. I have not looked back. My truck sat outside for over 20 years and the transmission works fine after we restarted it last year. That would not happen with a auto transmission. My 16 year old son likes the 4 speed. He thinks it is "cool".
 

Joe383

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I would keep the transmission too or swap over to a NV4500. There very strong and will add an over drive. If he ever plans on doing any 4X4 the 4 speed will be better at climbing it has something like a 6.5:1 first gear as the TH400 is only 2.48:1 the M465 will probably get a little better fuel mileage too not much but it will a little. If I was going with an auto though I would totally agree with MadOgre the TH400 is the way to go. Another thing if you go with a large cam you don't have to worry about if the cam is too large for the converter if you keep the 4 speed and if you get a cam that's a little large and you loose a little low end the 4 speed will be way more forgiving of it.
 

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