The Cat Scheduled Oil Sampling Game

In this game you control a bulldozer that rides around and pushes dirt.
Each dirt pile represents a "job". To keep from exploding you have to send in oil Samples to the cat dealership, then you will be told if the oil is good or bad. If you fail to do this occasionally your oil will go bad and you bulldozer will explode. To clean the oil you have to go to the cat dealership. You might also need some repair !
The goal of the game is to make the most money from finishing "jobs".