Does it matter? I think the double pump was a dealer-installed option, anyway.
Not as far as drawing a vacuum it doesn't, and yes, this double acting pump was a "new" add-on for my truck, as it was just installed last week.
My question wasn't intended to start debate, it was simply posted in hopes of getting ideas and the chance of seeing a photo or two. Since the pump is mounted low on the engine and in an area subject to oil leaks (the pan) I was just wondering if perhaps it was tubed way back then.
Don