Yours truly has a neutral opinion regarding engine flushes: I believe engine flushes are only necessary when the engine has sludge buildup. Sludge is a dark and thick substance from contaminated oil, ...

The oil inside your car's engine can sludge up with neglect and infrequent oil changes. Sludge is a nasty contaminant that can destroy an engine if not given attention, but timely oil changes are a ...