When I did the math years ago on this the deciding factors were price difference and similar economy.
This was back when it was recommended to do oil change on turbo diesels every 5k vs 10k for patrols.
If the 2 vehicles got exactly the same mileage, it took 20000 or so k's a year to start to be cost effective.
This was back when diesel had just risen from maybe 2/3rds the price of petrol to approx 3/4.
My reckoning is that if it is all but the same price, RUC's wreck it. Unless you really need a diesel for towing etc then petrol starts to look more attractive.
Also well aware that a lot of those older diesel have issues with heads and head gaskets once they get up in the mileage. Reasoning the petrols not as bad especially if there is a large price difference between the petrol and diesel model in favour of the petrol.
Another thing that used to annoy me was how you would drive around with the cheaper diesel fuel then have to buy more RUCs. Tricks you into doing more than you might with a petrol and copping it at the bowser.
Bookmarks