Buick RIVIERA 1993 Manual page 236

Power Steering Fluid
What to Add:
Refer to the Maintenance Schedule to determine what
kind
of
fluid
to use. See
"Recommended Fluids and
Lubricants" in the Index.
How To Check Power Steering Fluid:
Unscrew the cap and wipe the dipstick with a clean rag.
Replace the cap and completely tighten it. Then remove
the cap again and look at the fluid level on the dipstick.
When the engine compartment is hot, the level
When the engine compartment is cool, the level
should be at the "HOT" mark.
should be at the "FULL COLD" mark.