Well I lost about 6 quarts of coolant into the oil system in a matter of 5-10 minutes of running, but I don't have any trace of oil in my coolant. I have removed the oil cooler and am going to pressure test it, and I also removed one of the valve covers and noticed some traces of coolant there. Would this indicate a potential head gasket failure? What are some common things that I should test based on having coolant in the oil but not the other way around? Thanks!