Ford V-6 Teardown Shows the Catastrophic Effects of Prolonged Police Duty

There are multiple holes in the block, two pistons missing, and valves in the oil pan.

By: Christopher Smith

May 18, 2024 at 3:00pm ET

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Police cars live a tough life. They're driven hard every day, putting extra stress on things like powertrains and suspension components. So it's not surprising to hear the 3.3-liter V-6 in this 2021 Ford Explorer police car gave out after just 75,000 miles. What is surprising, though, is the extent of the damage.

This recent teardown from I Do Cars on YouTube gets right to the point, showing three sizable holes where none should be—two in the oil pan and one in the block. An attempt to turn the engine over by hand leads to loud thumps as items fall inside. Clearly there's some carnage, but we weren't prepared for the disaster sitting in this Ford's oil pan.

Finding any wayward bits of metal in the pan is bad. Sadly, this poor V-6 has a veritable scrapyard inside. Two pistons are pulverized to the point of being nearly unrecognizable, while small pieces of pistons, rings, connecting rods, engine block, and even part of a valve reside in the icky metallic cocktail below. Temperatures got so hot that a bearing was partially welded to the crankshaft. The noises this thing made in its death throes must have been painful.

While it's abundantly clear why this engine no longer functions, how it happened is an intriguing mystery. Evidence points to a bearing failure, possibly due to oil starvation. However, that would usually lead to small metal flakes being circulated through oil to the top of the engine. But the heads and camshafts look remarkably good. It also doesn't appear to be a hydrolock issue, as that wouldn't destroy bearings like this.

What do you think?

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The prevailing theory is that the engine was revved until it could rev no more. If the failure occurred while Pursuit Mode was active—a feature that automatically shifts into the lowest-available gear during hard braking. It's possible the downshift went a gear too far. A computer-controlled rev limiter wouldn't prevent that from happening, and such a sudden spin-up could lead to oil starvation.

The extensive damage in this engine certainly lines up with pistons careening wildly at a gazillion RPM without the benefit of lubrication. But it's just speculation. What do you think happened here? Let us know in the comments below.