Guys are doing it without negative results. hard to say for sure if they are having positive results. First, ATF is red. Off road diesel is red. I've never been "dipped" by DOT, but I'd hate to put ATF in my tank and have murphy strike and get dipped, testing positive for red dye and paying a huge fine.

The theory behind adding ATF is that the oil/lubrication helps your fuel injectors longevity, that today's diesels lack the oils and lubricants needed to keep them happy.

Another option guys use a lot of is 2 cycle oil mix added to the diesel, for the same reason, that it helps injector life. I've done it 2 or 3 times, but I wouldn't do it a lot. I was getting puffs of white smoke at start up, even when temps were 75 degrees outside. I ran a few tanks with a diesel fuel additive bought at the parts store. I ran a few tanks with 2 cycle oil mix, and a 5th tank with the additive again. white smoke puff at start up has gone away.