What size is the engine oil drain bolt on the 4.0 V6? I used a 9/16 but it seemed a little big. 14mm was too big.

One weird thing I noticed is that the Motorcraft FL820 oil filter has grooves on the bottom of it...but the factory-installed oil filter didn't! Don't they use Motorcraft at the factory? It made a big difference for me because I bought a new cap-style filter wrench but had to take it back and get a strap because it didn't fit!

Also, the stores around here don't carry Motorcraft fully synthetic oil, they carry the Synthetic Blend. Is the blend better than regular old oil?

 

Everything you need to know about engine oil

What Is The Difference Between Synthetic Oil And Conventional Motor Oil?

Try these sites it will help with your understanding of oil.

 

assembly line parts are sometimes different than their service counterparts.