so I bought a 2011 Ford flex and it runs well and everything...went to change the oil only to find out that the 2011 3.5 engine has a bigger oil filter thread hole....this motor has the 3/4 hole....and I was told at the parts store that type of filter was for the 2009 motor....so I tried it and it screwed right on.....my question is....how can I somehow find out how many miles are on the engine itself? The body has 173,000....but I need to find out what's on that engine. What a bummer
Frankly you want to know about the health of the engine.
Compression test, leakdown test, and pull the oil pan and valve covers.
Check for cam wear and sludge in the top end.
Check for metal particles and sludge in the bottom end.
And of course do a combustion gas leak test in the radiator/reservoir
how can I somehow find out how many miles are on the engine itself?
You can't unless there is some record of how many miles the engine had when it was installed and how many miles the car had on it at that time.
That's assuming the engine was actually replaced. Bear in mind that parts store databases are not always correct. You might want to check with a Ford dealer parts department.
Another concern may be the water pump. It's internal to that engine, driven by the timing chain. If it starts leaking, coolant will get into the oil and destroy the engine. Replacement requires major disassembly.
https://www.youtube.com/watch?v=R3-NOGZL8ms
