2007 Cadillac STS Owner's Manual - Page 512

(n) Visually inspect belt for fraying, excessive cracks, or obvious damage. Replace belt if necessary. (o) Drain, flush, and refill intercooler system. This service can be complex; you should have your dealer perform this service. See Engine Coolant on page 389 (p) For supercharged engines only: Have your dealer check the supercharger oil level and add the proper supercharger oil as needed (or every 36 months, whichever occurs first). See Recommended Fluids and Lubricants on page 516 Owner Checks and Services These owner checks and services should be performed at the intervals specified to help ensure the safety, dependability, and emission control performance of your vehicle. Your GM Goodwrench® dealer can assist you with these checks and services. Be sure any necessary repairs are completed at once. Whenever any fluids or lubricants are added to your vehicle, make sure they are the proper ones, as shown in Recommended Fluids and Lubricants on page 516. 512