Is Long-life Servicing Causing a Long-life of Problems?
As with any new vehicle purchase, running costs are always a contributing factor with any decision especially as sometimes large amounts of money are involved. Tax, insurance, fuel consumption is the first things we think about, but running costs of say, a Tyre or a routine Service for example can be secondary and often forgotten.
Unfortunately vehicles with long life service schedules are not as well made as they were, as the focus is more on cost saving. Due to the tighter demands on emissions, performance and fuel economy. Most materials are now lighter, thinner and this is also the case for engines. Engine design has evolved, the improved metering of fuel injection and turbo efficiency, alongside to decreased weight has improved performance considerably both in power and economy.
For these reasons, more demands are placed on engines and the oil it uses.
Long-life Servicing takes into account that technologies have improved in both engine and oil design. With this advancement, it’s now possible extend each oil change twice as long as before…. but should it?
Here at SWSS BMW our experience is that it shouldn’t.
Many of today’s petrol engines (of which BMW was one of the first) implement a valve train system that is operated using oil pressure to adjust camshaft timing and maximise engine performance. This is done through an electrical solenoid controlled by the engine ECU, allowing a certain amount of oil into what’s know as VANOS unit fitted onto the camshaft.
The VANOS units acts independently to the main engine’s timing gear and turns the camshafts to open the valves at different engine loads, thus, improving torque and economy.
When the Oil is fresh and at the correct level these advanced engine systems can work reliably and effectively. From our experience at SWSS BMW, oil condition and its level is not monitored and we see a number of engine related diagnostic problems, simply resulting from low oil. It is often the opinion of customers that engines do not consume oil but because of the higher demands, tighter engine tolerances, it is quite normal to see quite frequent top ups between intervals. On some BMW engines it is normal to see a litre per 1000 miles !
“ we see a number of engine related diagnostic problems, simply resulting from low oil.”
Long-life servicing has been around a number of years and has lowered the cost for mainly vehicle lease companies and for the dealer servicing plans which makes it attractive from a sales point of view.
Engine oil has a number of important purposes, namely to lubricate essential moving components, collect dirt, reduce wear and friction. However there are a number of other tasks required such as, keeping the engine clean, preventing corrosion. All of which is vital to keep the engine running at maximum efficiency.
Because engine oil prevents friction, this intern lowers the temperature internally as it moves through it. This means that the engine stays at a consistent temperature rather than having cold or excessively hot spots helping performance and fuel efficiency.
Even though engine oil is designed to fight against wear and metal friction, small abrasions still exists and these particles are carried within the oil. Even though the Oil Filter is designed to remove these particles, it cannot be 100% efficient in doing so. As these particles circulate within the oil, these particles create additional abrasions creating more wear.
We often see BMW’s in our workshop that have covered over 20,000 miles before the replacement of fresh oil. It can be said that oil technologies have improved over the years because of research and development. However the ask of oil to deal with the higher combustion temperatures, pressures, turbo charging, DPF regeneration, varying climate conditions along with keeping the engine clean and providing lubrication over a 2 year period is big requirement.
Another thing we see here at SWSS BMW, are vehicles that cover only small mileages. There’s common misconception that an oil service is not required because it may have only covered say 6000 miles in the allocated 2 year interval and although this might seem logical, it is the worst type of scenario for an engine and its oil.
When a vehicle is driven for short distances, the engine doesn’t have an opportunity to warm up correctly and as a consequence, build up fuel, carbon and moisture becomes more and more apparent in a relatively short time. This will create greater wear than an engine which covers a much higher mileage that is serviced regularly and driven at full operating temperatures.
Here at SWSS BMW we recommend that engine oil is replaced at least once a year regardless of mileage. Furthermore there have been many theories that a large number of problems with timing chain wear issues, such as the Diesel N47, are down too long intervals and poor servicing, together with cheap oils.
Here at SWSS BMW in Cardiff, we can advise you accordingly and we can also check your vehicles history via BMW’s Database. Every Service we carry out at SWSS is recorded with BMW including your vehicles iDrive.