Chevrolet 2000 C-Series Owner's Manual page 220

R
Coolant Recovery Tank Surge Tank (Caterpillar Diesel Engines)
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(Gasoline Engines Sloped Hood)
When your engine is cold, the coolant level should
be at 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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