We have a 2021 Ford Edge SEL AWD. I'll be under it in a couple hundred miles to do an oil change and thought I might as well do a PTU drain and fill while I've got access to it. My question is what weight gear oil goes back in? I look up my vehicle on the Amsoil website and it shows 75W-90, but also shows 75W-140. A few Google searches show 75W-90. A search on Advance Auto's website with our car's info shows 75W-90. Every Youtube video I can find closest to our 2021, a 2020 model year, shows replacing the oil with 75W-140. Can someone please help me determine which weight oil is right, or whether it matters, so I can have it on hand before my oil change? Has the 2021 model year PTU changed from the 2020 model year PTU along with the recommended fluid? Appreciate in advance any help you can provide.