Awhile back, I got an e-mail from an old friend, brief and to the point: Write about this. This, it turned out, was transmission fluids and the great confusion that exists in the marketplace today about what products to use in what vehicles.
With the e-mail were two attachments. One was an SAE paper from 1937 (I kid you not) on the subject of clearing up the confusion about transmission fluids. The other was a spreadsheet citing over 200 transmission fluid specifications running from A to Z; that is, Aisin Warner to ZF. Quite a few of these specs are regarded as obsolete – such as Allison C-3 or Ford Type F fluids – but some vehicles out there may still require their use, at least according to their owners manual.