Help me decide on a new purchase..3.0 or diesel?

[JCL]

Originally Posted by nosnoop

Do the service and maintenance intervals differ between diesel and petrol?
And does diesel have more problem in extreme cold weather than petrol?

bigX5er answered, but my thoughts from 20+ years of diesel service experience (not on BMW) are:

The service intervals do not have substantial differences. Unscheduled items such as fuel filters are more likely to be required on a diesel, but that shouldn't be enough of a reason to pick a diesel or not.

Diesel fuel has more problems in cold weather (it gels at low temperatures). Winter diesel blends are designed to address that problem, but they often come with a mileage penalty (winter diesel usually has lower energy content). You may see anywhere from 0 - 10% reduction in fuel mileage in winter. Modern diesel vehicles have heated fuel systems to deal with the fuel issue, but there is the potential for some difficulty, and the additional systems are one more thing that can fail, impacting overall reliability. Depends somewhat on how cold it is where you are. Diesels also like to be run warm, which is why trucks often have winter fronts on their grills to restrict cold air flow. In very cold weather you need to make sure the vehicle has time to get fully warmed up, ie your trip is sufficiently long. Idling it to warm it up doesn't help.