TH400.  <a href="https://en.wikipedia.org/wiki/en:Turbo-Hydramatic" class="extiw" title="w:en:Turbo-Hydramatic">Turbo-Hydramatic</a> 400 Transmission.  This is a 3 speed automatic transmission made by <a href="https://en.wikipedia.org/wiki/en:General_Motors" class="extiw" title="w:en:General Motors">General Motors</a>.
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/24374232@N00">Vic Brincat</a>
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