My dad has a Jeep 4.0L and it has about 14K miles on it. It has been running on dino every 3k miles. He is thinking of going to synthetic and changine it once a year. He averages 4k miles per year on it.
Do you think in this case a flush should be used before putting Amsoil 10w-30 in?
Do you think in this case a flush should be used before putting Amsoil 10w-30 in?