2004 Pontiac GTO Owner's Manual - Page 226

Power Steering Fluid How to Check Power Steering Fluid The fluid level should be checked after the vehicle has been driven for at least 20 minutes, so that the fluid is warm. A convenient time is when stopping for gas. The cold level check should only be used after the engine has not been running for at least five hours. However, the hot level check is always recommended. The fluid level can be viewed through the reservoir. The level markings are next to the fluid window. When the fluid is cold the level should be between the COLD MIN and MAX marks; when the vehicle has been driven for awhile and the fluid is hot the level should be between the HOT MIN and MAX marks. If fluid must be added, undo the cap counterclockwise to the stop; then the cap can be lifted off. Do not overfill and remember to replace the cap tightly. If you often need to add fluid, you should see your dealer. Remember to secure the cap when the level is correct and clean up any spillage. When to Check Power Steering Fluid See Engine Compartment Overview on page 5-12 for reservoir location. It is not necessary to regularly check power steering fluid unless you suspect there is a leak in the system or you hear an unusual noise. A fluid loss in this system could indicate a problem. Have the system inspected and repaired. What to Use To determine what kind of fluid to use, see Recommended Fluids and Lubricants on page 6-13. Always use the proper fluid. Failure to use the proper fluid can cause leaks and damage hoses and seals. 5-36