OK, I was changing the oil and filter in my ’88 4.0L today, one would think the easiest thing to do, right? I had two WIX 51626 filters (was going to change the '89 also), both would not thread on, they seemed slightly big, I could feel the threads pass each other. I checked the IDs, ~0.735 for the old Fram PH3985 (I know, I know) and ~0.747 for the two WIX. I then went to NAPA, got a 1626 Gold series (made by WIX) same thing, so I got a cheap STP S3985 from Autozone, same thing too big, WTF?? The old Fram spins back on so nothing is wrong with the mount, my ’89 has a WIX 51626 and my ’90 has the NAPA Gold 1626. I guess its par for 2020. So now I'm in a holding pattern until I get one that fits. Anyone else have issues with oil filters lately?