Wynn’s Engine Sealant maintains excellent engine oil fluidity during low temperature starts. It will not reduce pumpability or cold-cranking ability below freezing temperatures. Wynn’s Engine Sealant improves the viscosity index and high temperature viscosity to reduce oil seepage caused by loss of oil viscosity. It controls internal oil consumption while it conditions, and gently swells rubber seals and gaskets to stop and prevent l oil leaks.