When it comes to going to the garage for an oil change, perhaps some of your customers prefer it to be quick without necessarily thinking about extending the life of their vehicles.

We know that some customers tend to praise speed of execution without taking into account the quality of work and the vehicle’s maintenance record.

Here is how this simple service could benefit you or not.

Check the lubricant level

As a first step, I think it would be a good idea to check the engine oil level before changing the oil. We know that maintaining the oil level in an engine is vital to its operation and longevity including lubrication of engine parts, turbo, variable timing solenoids and multiple sensors. It is equally important to pay attention to the quality of the oil you use, of course.

Probing the oil level and finding it low will not necessarily be a significant sign of overconsumption, but may have some connection to people’s driving habits.

The customer will probably not understand what fluid dilution oil contamination is, that poor filtration or even engine ventilation could cause engine seizure or turbo main shaft failure as a result of this low oil level. These results can also be seen by poor oil pan ventilation (Power Cranking Venting) on some models, which means that an engine needs to be vented. A good job for technical consultants, but … if only you had taken the time to explain it to your client.

Oil pan ventilation

Symptoms of a poor PCV are either a rough idle, a slight engine hiss at certain engine speeds or an increase in internal engine pressure. They can also be betrayed by moisture accumulation, leaks or abnormal oil consumption. Sometimes they can be recorded as an anomaly code from a system to suspect a faulty sensor.

For some models, it is not always pleasant to check the PCV, especially when it is coupled to the valve cover or with a variable cam system. When this happens, you will have the opportunity to put your diagnostic knowledge to use. Let’s not leave our knowledge in the drawer and remember that to check this simple piece of plastic, it’s handy to know how to diagnose it, either by idle fuel correction, history or undetected misfires, all without a warning light on the dash.

A case in point

Mr. Ouimet (pronounced like “Oui, mais” in French, meaning Yes, but…), following an oil change, came to the garage a few months later and complained of a slow and difficult start. A beautiful BMW 5 series with an unstable idle and no warning light on the dashboard.

After several checks, it turned out that the ventilation pipe of the PCV was clogged with metal particles. These particles come from the top of the engine due to a lack of lubrication because of the low oil level. In short, the engine is at the end of its life due to neglect of recommended vehicle maintenance.

I repeat that you should always check the oil level of an engine before changing it. If the oil level in your customer’s vehicle is low, it would be wise to indicate this on the invoice as a preventive measure and thus avoid having to repair breakdowns that could have been avoided.

The customer’s response was “Yes, but… you are the one who worked on my vehicle lately!”