hotrodg726· Premium Member
1956 chevy 210 del rey sedan
Pops is correct here. drain it and refill with conventional oil. synthetic will not let the rings seat properly or maybe at all. usually leads to glazing the cylinders. If it were me, I would drain and refill and replace the oil filter. that should be sufficient. better safe than sorry. Save the synthetic for after the first 1500 miles. and for the cost I would only use mobile 1 not that penzoil garbage.If this is a brand new rebuilt engine, I would not be breaking it in with synthetic oil...(ZDDP added or not)
This would be a better choice IMHO: Robot or human?
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