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lou's garage

Hi Lou,

I enjoy your column.

We have a 2.5-litre 2014 Subaru Forester and my daughter has a 2020 Subaru Outback. My neighbour also bought a 2021 Forester. These all have the 2.5-litre engines and all three are serviced at different Subaru dealers. Every time the dealer overfills the oil sump on our car. My daughter and neighbour say they have the same problem.

Our car’s holds 4.8 litres and every time they put in 5.5 litres. I have complained to our dealer, but it keeps happening. Is there any damage caused by this overfilling?

Thanks – Arnold A.

In short, overfilling an engine by a generous amount is going to cause damage. However, a small amount like what you have been experiencing will typically not cause any damage because manufacturers build in a buffer, knowing that sometimes their engines get a touch overfilled.

Here are two stories that show how such a mistake can happen, but in both cases it was much worse than just a small amount of oil.

A reader reached out asking for help a couple of months ago about a problem they were having after their Subaru suddenly died.

A young inexperienced technician at an automotive chain repair store accidentally drained the vehicle’s transmission oil instead of the engine oil. He then filled the engine with 4.8 litres of oil. This would be in addition to the oil that was already in the sump, that he had mistakenly not drained, meaning this engine now had twice the amount of oil that it was supposed to have. To make matters worse, the oil level wasn’t checked and the customer drove away, only to have the car start smoking heavily and lose power a few blocks from the shop. It was towed back, and the repair facility realized the error and confessed. They said it was a minor oversight and that it had been corrected and sent the owner on their way again. The customer left and a short time later the car started acting strangely and lights came on the dash. Because the owner was on the highway, they didn’t feel it was safe to stop and limped it off the highway running poorly. But it was too late, the engine had just expired.

The repair facility acknowledged the fiasco was their fault and initiated an insurance claim with their garage liability insurance to cover the costs of replacing the engine. However, instead of just replacing the engine the insurance company decided to write-off the car, claiming it as a total loss because the cost to replace the engine was close to the value of the car.

According to the reader, the insurance adjuster stated that because the owner didn’t stop on the highway and tow it immediately that they were partly responsible for the failure. The insurance company was unwilling to pay the full amount, leaving the owner in a jam as they couldn’t afford to replace the car or the engine with the amount being offered. They reached out as they were preparing a lawsuit, seeking my professional opinion. In my opinion, road safely is always the primary goal, dealing with the aftermath is secondary. The repair facility should have never let the car go the second time without a lengthy test drive to ensure it was indeed fixed.

After reviewing their documents and hearing their story, I offered to speak with the insurance adjuster before things escalated to small claims court. I did not feel that the owner of the car should be expected to be left with any out-of-pocket expenses for this nightmare. The insurance company agreed with my point and offered the owner an appropriate settlement value which the owner accepted.

My own personal story is similar. When I was a young technician at an Acura dealer, I started an oil change on a car and had just got the vehicle inside and up in the air when I was reassigned to another more complicated repair. An apprentice was tasked to complete the oil change. They assumed I had already drained the oil and proceeded to add another four litres without checking the levels and sent the owner on their way. The engine did the exact same thing as above a short time later. I was initially blamed, but reminded the manager he had reassigned it, diverting his focus to another employee.

A technician has to walk around the parking lot looking for the vehicle, bring it in and get it on the hoist, drain the oil, go to the parts department to fetch an oil filter, fill the oil, perform a standard 30-point inspection, set tire pressures, top up fluids, reset maintenance minders, do the necessary paperwork and get it back outside. And all this in less than 30 minutes. Most dealers have some sort of dedicated oil change lane these days, but often those lanes are so busy that overflow goes to regular service bays.

In your situation Arnold, the Subaru parts department staff sets the engine oil-dispensing system to discharge 4.8 litres and it is usually quite accurate. The problem is that the technicians likely become complacent, depending on the accuracy of the oil-dispensing system and sometimes don’t thoroughly check the oil level. They just put the oil feed hose into the engine and let the predetermined amount fill the engine with 4.8 litres. However, if a little bit of oil was leftover and not drained properly you will be slightly overfilled which is what I suspect is happening with your service visits.

In these examples it was human error, but having seen both sides, it’s a tough scenario to win.

Yes, the bulk of oil changes are done by junior staff. I remember the horror of having less than 30 minutes to perform all those tasks on scorching hot engines a dozen times a day. Fall behind and you were scolded for being too slow, make an error and it was your fault too.

Lou Trottier is owner-operator of All About Imports in Mississauga. Have a question about maintenance and repair? E-mail globedrive@globeandmail.com, placing “Lou’s Garage” in the subject line.

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