I'm looking for a new or used transmission for a 1997 Ford heavy duty truck with a Catapillar engine?

I'm looking for a new or used transmission for a 1997 Ford heavy duty truck with a Catapillar engine? - 1

You need to know what type of trans the vehicle has & since you probably don't have an owners manual, it will be more difficult… If you can get any #'s from the trans case or take some photos for a truck repair shop to see, then that would help… Presuming that there's a trans now in the truck, you can get it rebuilt

The best I can tell you it came with either an Allison, Clark, Fuller, or Spicer transmission. Your best bet to call or email Ford and ask what transmission came with your MEDIUM duty F600 or F700.