I changed the oil in my 67 coupe on Saturday and I now have a knock in the engine. I've had the car for several years and the engine has been bullet-proof. I put in Valvoline 10W-30 with a bottle of ZDDP. This is the first time I've added the ZDDP. Could this be my problem. The engine is a 302 that I believe is from a '71.
As I said, this engine has never given me any trouble before. Any help would be appreciated.
As I said, this engine has never given me any trouble before. Any help would be appreciated.