Diesel engine oils contain high levels of detergent and dispersant additives because diesel ... important when determining the right viscosity oil to use. That's right, 20W-50 is not a one ...

Choosing the right oil can make or break your engine ... SPEEDiagnostix also included a sample of a 30w non-detergent oil that is obviously not a good idea ... Oil Analysis. Castrol 20w50 SN.