Originally Posted by JonF1982
Depends how many miles you do. New efficent petrol engines will work out more cost effective if you're doing less than 10,000 miles a year as you never make back the extra cost in buying the diesel in the first place.
At 10,000 to 12,000 a year there is very little in it either way. Over 12,000 you wan't a diesel.
Obvioulsy only by properly breaking down the figures with a calculator and knowing the MPGs and having a fixed price for fuel (which we wont ever have) could you know exactly, but that's a rough rule of thumb i go by.
There's also the residual value to think about throwing another spanner in the works.
I agree, we must crunch the whole ownership numbers, to see where the petrol vs. diesel costs merge and/or cross over.
I've just moved from a 330d to a 535i and the fuelling cost is the least of the issues, at about 8k miles per year. For me, it is about 10% more to fuel the petrol 535i. That is 2 - 3 pence per mile. Which is really nothing in the grand scheme of things, whether a 3.0d or 3.0i, where the real running costs for either
are in the region of £1 per mile.
Changing cars and how we do it, (like new vs. nearly new) is where the real cost comes in. The OP will pay heavy just to change engine type, if he goes ahead, whatever the difference in engine characteristics or change in fuel costs.