• All cars, even those with latest stop-start engine technology cannot perform at their best in traffic congestion. And congestion has dramatically increased over the past 10 years, causing engine wear and wasting fuel. Suitable for the latest stop-start engine technology, Castrol magnatec stop-start  combines dualock molecules with our most efficient, fully synthetic base oils to dramatically reduce wear by 50%* and save up to 60L** of fuel a year in congested driving, thus ensuring non-stop protection from every start.