All Ford Superduties with a manual are the ZF6. I believe previous models were the ZF5 but I don't direct experience with that.

I was going to suggest destroked.com as well...

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-Evan


Benz Fleet:
1968 UNIMOG 404.114
1998 E300
2008 E63


Non-Benz Fleet:
1992 Aerostar
1993 MR2
2000 F250