See also:

How OnStar Service Works
Automatic Crash Response, Emergency Services, Crisis Assist, Stolen Vehicle Assistance, Vehicle Diagnostics, Remote Door Unlock, Roadside Assistance, Turn-by-Turn Navigation, and Hands-Free Calling ar ...

When to Check Lubricant
It is not necessary to regularly check rear axle fluid unless a leak is suspected or an unusual noise is heard. A fluid loss could indicate a problem. Have it inspected and repaired. All axle assembl ...

Hydraulic Power Steering
Your vehicle has hydraulic power steering. It may require maintenance. See Power Steering Fluid on page 10‑21. If power steering assist is lost due to a system malfunction, the vehicle can be s ...