3 quarts G-oil working for me, so far.
- It's been about 500 miles since my change to G-oil. Plus I had them only put 3 quarts in the car. At the same time I had my transaxle oil changed with standard Toyota transaxle oil. Along with the coolant changed to the pink stuff in both engine and inverter sections.
I imagine all those changes added up to improve my gas mileage 5-10%. Before the change in the very cold weather I was getting around 33MPG and now getting about 36MPG (reset after gas fillups). I have only made one highway trip since the change and the 5 minute bars on the screen were mostly above the 50MPG mark with one 5 minute bar reaching 75MPG. I don't think I have ever peaked 75MPG/5min. on the highway before. I must have been going down hill or had a tail wind or something.
I'm sure when the weather gets warmer my MPG will improve to the normal 40 something MPG range. One thing the car is riding smoother. When I'm coasting to a stop I have to use my brakes more because the car feels like it's gliding more since the 120K mile oil and coolant changes.