I doubt you have anything to clean out. From my experience, Valvoline conventional tends to burn off well before it sludges. Someone else already mentioned the timing chain and guide wear is mainly from running the car low on oil. I see it a lot in Cadillac owners who consistently run the oil life percentage to zero without checking the oil level.
For DIY, Maxlife is a much better oil and deal IMO. For around $2 more you get a synthetic blend and arguably the best high mileage oil available. Why not run that for 3-7k mile OCI especially considering you burn about 1 qt every 5k miles (completely normal and benign consumption)?
For DIY, Maxlife is a much better oil and deal IMO. For around $2 more you get a synthetic blend and arguably the best high mileage oil available. Why not run that for 3-7k mile OCI especially considering you burn about 1 qt every 5k miles (completely normal and benign consumption)?