Engine oil is one component in a car that everybody knows. It’s readily available and anyone can ‘top up’ as it’s easy to put in.
There’s a huge difference in oils available and the requirements of different engines; Standing in a fuel station with the choice of 10 different oil types with viscosity ranges of: 0w-60, 20W-60, 0W-40, 5W30, 10W-40, 15W-40 and specifications for each viscosity of: ACEA A3/B3, A3/B4, C3 or API SJ, SL, CE and CF, to cover just a few can be a bit confusing. Especially when you just want to put a bit of oil in the car. You may use the same method I do when I’m buying wine………I go on price and the assumption that the more expensive it is the better it must be.
10 years ago a bit of 10w-40 or something close would probably do, but in the drive to cut emissions down, engine technology has increased massively. They run hotter, leaner, have extended service intervals with tighter tolerances and as a result the technology built into that golden fluid that we can all pour into our engines has increased massively too.
The worst issue in oil (apart from the environmental impact) is having no oil in the car – so something is better than nothing. But only in the short term! It is critical that the oil specified in your hand book is the oil put into the engine at service intervals. Some cars will use almost no oil between services, others will have weeps, and some will use up to 1 litre every 600 miles until they are run in properly. NEVER wait for the oil warning light to come on, the engine can be lubricated on little ore than a coffee mug worth at that stage.
If you are ever in the oil aisle, with too much choice and unsure which grade and viscosity to put in, please give us a call. We can tell you what to put in from your registration number.
A recent Mercedes we had in with a ruined engine due to either lack of oil changes or the wrong oil. Diesels suffer from carboning their oil. This is due to the scraper ring on the pistons (that should act like a birds wing as the piston rises and falls) becoming carboned which then allows the explosion in the cylinder to leak past the piston and into the sump. This saps engine power and makes the oil black. In turn the oil looses ability to protect the moving parts as it turns into sludge.