Oil should be replaced before the normal service interval in very cold climates or if there is a burnt smell. Cold temperatures can thicken oil, while an unusual odor may indicate oil degradation. Warm climates do not typically necessitate earlier changes unless problems arise. ;
Oil should be replaced before the normal service interval in a very cold climate or if there is a burnt smell indicating oil degradation. Cold temperatures can thicken oil, while unusual odors suggest potential engine damage. Therefore, options A and D suggest conditions where earlier oil replacement is necessary.
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