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Cold Crank Viscosity
ASTM D5293- Test Method for Apparent Viscosity
of Engine Oils Between -5 and -35 C Using the
Cold Crank Simulator
This
test method covers the laboratory determination
of apparent viscosity of engine oils at
temperatures between –5 and -35C and at high
shear rates. The results are related to engine
cranking characteristics of engine oil. A
measured amount of sample is subjected to an
extreme low temperature for 3 minutes. The
rotor spins for 1 minute in the sample and the
speed of the rotor is measured by keeping ohms
resistance at zero. The speed-reading is used
to determine the viscosity on a calibration
curve.
The cold cranking
simulator (CCS), ASTM D5293, correlates with
engine cranking speed at low temperatures.
Cold cranking
viscosity simulates the viscosity of an oil in
crankshaft bearings during cold temperature
start up.
Cold cranking
viscosity limits, determined by the CCS, are
defined in the SAE J300 Standard, as shown
below:
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