I bet it smoked a lot for a little while though. I finished a valve job on my old Mustang late one night and needed it to get to work the next day. About half way through putting the first gallon of anti freeze back in it I noticed it was 10-40. That was a bitch to clean out and I had to catch a ride the next day to get to work. They didnt stop laughing the whole drive and told everyone I worked with the story as soon as we got there. I would have done the same for him though