Cadillac CTS - Manual (Page 347)

When to Add Engine Oil If the oil is below the cross-hatched area at the
tip of the dipstick, you will need to add at least
one quart/liter of oil. But you must use the
right kind. This section explains what kind of oil
to use. For engine oil crankcase capacity,
see Capacities and Specifications on page 457.
Notice: Do not add too much oil. If the engine
has so much oil that the oil level gets above the
cross-hatched area that shows the proper
operating range, the engine could be damaged.
See Engine
Compartment Overview
on page 342 for the
location of the engine
oil fill cap.
Be sure to add enough oil to put the level
somewhere in the proper operating range. Push the
dipstick all the way back in when you are through.
V6 Engines
V8 Engine
347