3spd Auto questions/ideas

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Aug 31, 2019 | 10:24 PM

VancouverXJ6

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From: Vancouver

3spd Auto questions/ideas

I have a spare 3spd v12 auto transmission, TH400 I think? What can I do with this?

Can I transplant the guts from a better transmission into the 'shell' ? Ask a shop to add more gears? Transmissions are a mystery to me so I have to ask.

Aug 31, 2019 | 10:44 PM

Doug

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From: Pacific Northwest USA

Quote:

Originally Posted by VancouverXJ6

I have a spare 3spd v12 auto transmission, TH400 I think? What can I do with this?

Can I transplant the guts from a better transmission into the 'shell' ? Ask a shop to add more gears?

No and no

Quote:

Transmissions are a mystery to me so I have to ask.

There are countless upgrades for the old 400 (introduced in 1964) but they don't include adding more gears. GM itself did that in the 4L80 transmission....but it was a fairly major redesign. The 400 roots and heritage remained but resided inside a new case, with 4th gear and electronic shifting

What can you do with it? Not much, really. Sell it or hang onto it. Maybe have it rebuilt and ready to install when your existing trans gives out?

Cheers
DD