Diesel engines may require more frequent oil changes and fuel filter changes than gasoline model vehicles, and some diesel cars may also require periodic replenishing of diesel exhaust fluid (urea), which reduces emissions of nitrous oxide. For the most part, though, diesel-engine cars follow the same maintenance schedule as gas engines.
Volkswagen, for example, says the oil and filter should be changed every 10,000 miles on its diesel models — same as the oil for gas versions. However, the schedule for diesels also calls for a fuel filter change every 20,000 miles. In addition, the diesels available in the Passat and Touareg need a urea tank refill every 10,000 miles (the 2.0-liter TDI engine in other models doesn’t). Volkswagen provides free maintenance the first three years/36,000 miles, so the first round or two of diesel maintenance for these cars is on the house.
Porsche recommends an oil change every 10,000 miles for its gas engine, but for the 3.0-liter diesel available in the Cayenne SUV it’s 5,000 miles.
Ford offers diesel V-8s in its F-250/350 heavy-duty pickups, and though oil-change intervals are the same as trucks with gas-fuel engines (10,000 miles or at least once a year), for severe driving (such as towing) Ford says to change the fuel filters on diesel-powered trucks every 10,000 miles as well replenish the urea.
Some Mercedes-Benz diesel-engine model vehicles also use urea injection systems that need to be refilled every 10,000 miles.
Maintenance schedules vary by manufacturer regardless of engine type, so it’s a good idea to ask to see a schedule while vehicle shopping. If the information isn’t readily available from a salesperson, the dealership’s service department will have it.