How long will a diesel passat last?

Answer 1

Close to forever if it is properly maintained. The biggest killer of diesels is over heating. Never, NEVER let it overheat. Next, because the fuel is a low grade lubricant, it burns a bit dirtier than other fuels (but less pollutant per mile) and therefore needs to have the oil changed religiously every 3,000 miles with a new oil filter each time. If you live in a northern climate, you should change the fuel filter every spring (to get rid of the coagulants and moisture that might have built-up during the winter) and every fall (to insure that it starts out the winter with a clean full capacity filter - not much else worse than trying to change the fuel filter while standing in slush on the side of the road and then trying to re-prime the pump with a tired battery in the cold). If you live in the deep south, you might get by changing it every year. The air filter protects grit from getting in the engine and prematurely wearing it out, therefore insure that the air filter is clean and when it is not, replace it. Do your standard lubrication of the grease fittings, and your VW diesel should give you a lifetime of enjoyment. I have had a few of them with over 350,000 mile before they fell victim to accidents or the erosion of road salt. Also, people have let others borrow their cars and the new drivers either did not realize, or did not remember that they were diesels and filled them with gasoline. The diesel will run for a long way, or at least a day or so on gasoline and then the seals in the fuel pump will dissolve. If this happens, some will give bad advice (replace engine, etc.), but you only need to flush the fuel system, replace the filters, and rebuild the pump with new seals. That my be a lot, but it is not near as bad as some will have you believe.