Do Dealers Change Oil Before Selling? (You need to know this)


Buying a pre-loved car can be stressful, after all, it’s a major purchase. And you’re correct to ask about oil, it’s one of the most important car fluids. 

Most reputable dealers will change the oil and oil filter before the customer takes delivery of their new pre-used car. The digital onboard service record and the maintenance section of the driver’s handbook will detail maintenance completed and scheduled.

In this post, you’ll know how to check if the oil has recently been changed.

Reputable garages will change the oil and filter and a full safety check before selling a used car. Owning and operating a car dealership is an expensive business, it’s a major investment of capital, time, and talent. 

Most car dealers will guard their reputation, cutting corners like not changing engine oil isn’t good business. Bad news travels fast in the digital age, word of mouth is still a big driver of sales.

How Do Dealers Prepare Used Cars?

Chevrolet engine

I’m a mechanic for over twenty years and I’ve worked at a few big dealerships. In my experience, used cars are professionally prepared for resale.

At the dealers I worked at, used cars get a full safety inspection which is quite rigorous. Tires, brakes, suspension, and steering. If the car has been previously damaged it is not sold from the lot, instead, it‘s sent to auction. 

Maintenance records are checked for service due date for items like oil & filter changes, spark plugs, filters, serpentine belts, timing belts, brake fluid changes, coolant change, transmission filter change, etc.

Safety faults and oil and filter changes were always taken care of, without question. In our workshop, the foreman made a determination on other service items depending on how far from their due replacement date.

If their due date was less than 15,000 miles or 12 months, the dealer went ahead with the work.

Pre Sale Tire Checks

Tires are cars only contact with the road are therefore is extremely important. Bad rubber is a common contributor to road accidents. As a result, they are rigorously inspected on all vehicles when they enter a modern well-run workshop.

Tire condition

The technician is looking at tire pressures, damage, and wear. But also the subtleties of uneven tire wear which can often point to alignment issues or worn steering or suspension components.

Punctures, underinflation, overinflation tire wear, tire wall damage both inside wall and outer, flat spots and ovalizing, are all common tire issues. A faulty tire can cause lots of strange symptoms from excessive road-noise, pulling, bouncing, vibration, and the list goes on.

Pre Sale Brake Checks

Most cars today run brake rotors and pads, some models may still run drums both only to the rear. Rotors and pads are superior brakes and offer ease of maintenance when compared to the older style drum brakes.

New brake pads fitted

Worn pads and worn discs are common brake maintenance issues. On inspection, the technician will measure brake pad wear and disk wear. Generally, if wear is more than 60% the dealer will go ahead and replace them.

Brake fluid is the next consideration, fluid attracts moisture as it ages. The moisture causes two main negative effects. First, it causes corrosion inside the brake components. Second and more serious, it causes a spongy brake pedal and reduces brake performance.

The Technician will recommend a brake fluid change every three to four years.

Pre Sale Steering Checks

Checking for steering free play and signs of fluid leaks is a big part of the safety checks. Worn ball joints is a common issue with higher mileage cars. Power steering fluid leaks also, although many newer models now come with electric-assisted steering.

Pre Sale Suspension Checks

The suspension carries the weight of your car, passengers, and luggage, and doesn’t get a rest. It’s permanently loaded, you could say it works hard. Worn out shocks, struts, strut mount bearings, springs, control arms, bushings, ball joints. They all need to be checked for signs of wear.

How To Check Cars Service Records

There are two common ways to check if a car is due to an oil change. A vehicle maintenance handbook and the onboard service light indicator.

All vehicles will have a handbook (avoid a vehicle without one). The book, located in the glove box covers all the user information. A maintenance section is included at the rear of the book.

Modern car dash clock

The maintenance or service book includes important information like maintenance items completed, who completed it, at what mileage, and on what date. The service may also detail the next due service date and what items require attention.

The second way to check your oil change due date is with the service reminder info center. Most cars today are equipped with a service reminder light. The light indicates the vehicle requires a service, however, many vehicles also include computerized onboard service information. The info is commonly read from the driver information center (dash display) and accessed by dashboard buttons.

The display will detail mileage to your next oil change and may also include a date.

Before buying any vehicle, it’s always worth investing few dollars to check the VIN number against a database. An audit with a company like VinAudit (links to VinAudit) will guard against Mileage fraud, Salvage rebuilds, Title washing, and Vin cloning.

John Cunningham

John Cunningham is an Automotive Technician and writer on Rustyautos.com. I've been a mechanic for over twenty-five years, and I've worked for GM, Volvo, Volkswagen, Landrover, and Jaguar dealerships. My passion is cars. I use my knowledge and experience to write articles that help fellow gear-heads with all aspects of car ownership, including buying advice, maintenance, and troubleshooting.

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