Dear Tom and Ray: Is it safe to add a few capfuls of denatured alcohol to the crankcase of my two older vehicles to remove oil sludge before I change the oil? -- Lorilee RAY: Is it safe? Well, I don't ...

Additives represent 15 to 20 percent of a gallon of oil with the balance being high-quality base oil. Additive packages play a key role in helping to keep an engine clean and protected from varnish ...

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 ...