We are running M1 drive clean 5000 5W-30 in our 2001 Impala with the 3400 engine that has 39K total miles. Thinking of using GC with Purolator Pure One filter next OC. I picked up 5 quarts of GC with PP1 filter at Pep-Boys on special, have not put it in yet. Only have 1.8K on oil and will wait until we have 4K on it. I think GC will be the best oil to get a very long life from this engine. I was planning on going to 8K OCI with GC. I maintain this vehicle very well, including the cooling system. There is no chance that it will ever be abused by over-heating. I am now wondering about the higher Zinc levels possibly damaging the catalytic converter. And if I should just stay with M1 drive clean 5000 5W-30 with 4K OCI?
Any thoughts along those lines? Is the Zinc in GC too much for the catalytic converter? This vehicle has never required adding oil during all past oil changes.
Any thoughts along those lines? Is the Zinc in GC too much for the catalytic converter? This vehicle has never required adding oil during all past oil changes.