Just did an oil pan gasket job on my 1992 Ford Ranger with the 3.0 L V6 engine. Saw this in the bottom end of the engine, cleaned all of the sludge out of the oil pan and no big chunk of metal was in there. Figured if this happened recently then there would be a big chunk in the oil pan. as far as I know, the engine has never been rebuilt, could this have been a factory casting error?

The truck was running about a week ago before I started working on it, ran strong and smooth, no coolant in the oil when I drained it out, no glitter in the oil either. Has excellent oil pressure. Also, I would think if a rod blew up at some point, they’d be a bunch of scratching and stuff all on the block??

Any thoughts about what this could be? Another thought I had was maybe it’s for oil to drain down from the top of the engine, and they just punched a hole out of there or something for it. I have a motorcycle cylinder head that has a hole punched out like this similar to the hole in the Ranger block, but after doing some research on that that hole is supposed to be there for air cooling on my motorcycle. So thinking maybe it’s something like that?

 

Looks like something punched thru there, but I would probably put it back together and forget I ever saw it if it ran good before

 

Yep, that's pretty much what I'm gonna do. It has ran flawlessly for the few weeks I've had it. I asked an auto tech instructor at the trade school I attend and he thinks it is a casting error. Personally I think if something punched through there like a rod, then there would be a lot of scraping all around the bottom end of the engine and I don't really see anything. I think the block may have come this way from the factory... If Ford saw this while assembling the engine (which I think they would it is pretty obvious) then they probably looked at it and determined it wasn't an issue and I guess potentially there could be a cavity there in the block that doesn't matter...

Anyways its going back together, I'm not going to swap a block or engine in a truck with 179,000 miles...

 

I've seen this before in intake valleys of Ford V8's. No way something could punch through up there, and the holes always looked similar to what you have.

I wouldn't worry about it.