Chevrolet B7 2001 Owner's Manual page 133

Checking Coolant
R
Surge Tank (Caterpillar Diesel Engines)
When your engine is cold, the coolant level should be at
Coolant Recovery Tank (Gasoline Engines)
the COLD level, or a little higher, on the coolant
recovery tank with the gasoline engine, or at the COLD
FULL mark, visible through the surge tank, with the
diesel engine.
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