Blue or grey smoke from the exhaust usually means oil is getting past worn valve stem seals or piston rings and burning in the combustion chamber. It is a wear problem, and on a high-mileage engine a proper repair is often not economic.

Greyhound Auto Retail stocks stop smoke additives that thicken the oil slightly and reduce the amount passing the seals and rings. They can noticeably reduce smoke and oil consumption on an older engine.

Be realistic about what these do: they manage a symptom rather than repair wear, and they are not a substitute for a rebuild on a badly worn engine. Nationwide delivery across South Africa.