Just how far can a Mazda 3 go without a service, 73,000km

[Olbucko]

I think that the owners of modern turbocharged diesels will be in for a very expensive shock if they don't service their cars on time. A diesel that only does short trips and never heats up properly contaminates it's oil very quickly with soot and should have it's oil changed every 5000km before it starts to thicken and block the filter and small oil galleries. If the same car was only used for long trips the oil would probably be good for 20,000 km. Also the particulate filter will never get hot enough to clean itself when only used for short runs causing it to block up and more horrendous expence.

In my own case I am happy to change the oil in my Territory every 15K as recomended by Ford, but I use synthetic oil and drive 45K per year so the oil change comes round every 4 months. I have followed the same routine in my Subaru which has now done 380,000 Kms and the engine still runs like new.

Keep em hot and filled with the best oil that you can afford and they will run for ever. (almost)