UPDATE: Instead of starting a new thread/post I thought I would just add to my original post.
As you can see, the Toyota oil seemed to be doing "ok" for wear. But I did not like how quickly it continued to thin out. And this civic engine has always been easy on oil! If you look, there was a time that the viscosity was 9.0 at about 1300+ miles. I know a lot of factors play into shearing but I thought that it began to shear quickly above 1300 miles according to the results.
I've also heard that this Civic engine likes moly, but Mobil (supplier to Toyota brand) switched to Titanium instead of Moly.
My fuel economy hasn't been good compared to where it should be. When the viscosity was at 9.0 my mpg's were higher! As it sheared down my mpg's went down with it.
I did a lot of research on this forum (thanks to everyone's data!) and I chose to try Castrol GTX 5w20, it's a very thick 5w20. And it has Moly!!
Even Blackstone commented that it looked like a thin 5w30. I know most will say to use a 5w30 because that's what it was spec'd for back in 96. But, the problem with that is. 5w30 was used and the engine began to have piston slap issues. After it was rebuilt, 5w20 was used. Since that time, no piston slap. It could be coincidental but I wasn't wanting to find out the hard way!
So I chose an oil that I thought was the best of both worlds, a thicker 5w20/thinner 5w30. I also didn't want to try a synthetic at this point, baby steps. Can't change too many variables right now.
Right now the mpg's have increased for this engine by 5.4 mpg compared to the oil oil, but I'll see if that's stable over the oil change interval.
Here's the current UOA:
