The terms Machining Rebuilding Repair are all used in the automotive industry, but include many different processes.
Repair is more basic, while rebuilding is more complex. And, either one may include some type of machining.
A Repair usually consist of replacing, only the faulty parts. Rebuilding includes, replacing all of the major and most of the minor components. Machining is the process of cutting, shaping, or removing material from a workpiece using a machine tool.
Machining Rebuilding Repair, are all procedures that can be done anytime your vehicle has problems. Depending on what the problem is and how much damage there is. Usually, the first thing that would be done is just a basic repair.