AoA People. Can you please guide regarding which oil to use? I have a 2014 Prius with original mileage of 155,000 KMs driven in JAPAN. I have used ZIC 10W-40 twice during the oil change after 3500 KMs each but I am not satisfied with the fuel performance. In the beginning it was giving me 24KM/h with AC but now in winters since it takes a lot of time to warm up which effects its fuel efficiency, it is now giving me 19KM/h. I am really concerned about it. Your help and guidance will be very much appreciated.
Ubaid ur Rehman