Reading around online and am interested in burning used motor oil in the truck, but mine is a 94 and I don't care to start replacing optical sensors every other week so if I were to come across a good used mechanical pump I could steal off a 6.2 would it work on the 6.5? From what I understand a db2 pump is a db2 pump 6.5 or 6.2 but want to make sure. This is just a fun project, I've got another truck and a saturn for a daily driver.

 

Although both 6.2 and 6.5 engines had the DB2 injection pump. There were few slight differences. One main difference is that the piston bore inside the pump is larger in the 6.5 pump. Another main difference is that the 6.2 pump works at around 1800 psi fuel pressure and the 6.5 pump works at around 2100 psi. Both are externally interchangeable, but usually the 6.2 pump isn't put on a 6.5. It will work, but probably not to your expectations.

Maybe you could try searching for a 92-94 6.5 mechanical pump. I would venture to guess that it would work better.