Hello I have 2002 GMC Denali pickup with a 6.0 engine. I expereince some noise at start up, but I also have noise @ about 1200-1300 RPM when the engine is warmed up. I have tried M1 5-30 and PP 5-30, but the noise is still present. The engine still runs strong, but I do not like hearing the engine noise. Do you think a 10-40 or high mileage oil would help eliminate the noise?