I have this new 2025 Toyota Rav4 that on the next oil change is going to get Castrol GTX synthetic. Of all the Castrol 0w-20 API rated oils, including their Edge products, it shows the highest viscosity ASTM D445 method at 9.0, I like that. As far as the 10,000-mile maximum oil change interval goes, it will never reach a 5000-mile OCI. I am hoping the little higher viscosity will increase the "cushy effect" ASTM ?, and make it seem a little quieter. And besides all that, I can go to my local Walmart and buy it off the shelf. I probably won't stick with it forever, as I tend to change oil brands like most people change underwear. I like to try the different brands. In the past, I have loved using Liqui Moly Top Tec 4600 5w-30, Schaeffer 9000 5w-30 and Royal Purple HPS 5w-30. The RP HPS was not API certified. It had their "Synerlec" potion in it. That was in my 2015 Honda CRV I traded in on this Toyota. Of the three in the Honda however, RP HPS was the best, then the LM 4600, then the Schaeffer. Anyhow, next is Castrol GTX synthetic 0w-20 in this new Toyota.