When adding fluid or making a complete fluid change, always use GM P/N1050017,1052884, power steering fluid or equivalent. DO NOT use automatic transmission fluid. Failure to use the proper fluid may cause hose and seal damage and fluid leaks.
If you live in an area with a colder climate, you may experience reduced power steering assist upon cold weather starting. This condition is caused by the viscosity of the power steering fluid on vehicles with longer hoses and should not be confused with conditions having similar symptoms. There is a "low temperature climate service fluid" (GM part no.12345866 or12345867) available if you fit into this category.
The power steering fluid level is checked by either looking at the marks on the see-through reservoir or by marks on the fluid level dipstick/reservoir cap, depending upon engine application.
When the fluid is cool, about 70°F (21°C), the fluid level should be at the full "COLD" or "C" mark. If the fluid is warmed up, to about170°F (77°C), the fluid level should be at the full "HOT" or "H" mark. If the level is low, add power steering fluid until it is correct. Be careful not to overfill as this will cause fluid loss and seal damage. A large loss in the system may indicate a problem. This should be inspected and repaired at once.
See Figures 1, 2 and 3