I've lost 3 chevy 350 engins in last 3 years. Used Penzoil 30 for years. I think it because of the lack of zddp. Filing a clame with them, will keep posted. As far as using Peenzoil, not again. Problems incured, droped valve, proable cause, worn valve guide, problem 2 lobe worn flat, 3 valve wore hole in rocker, resulting in droped valve. All lubricating problems.
