Should I buy a petrol or diesel BMW or Mercedes?

I feel it is time to treat myself and am proposing to purchase either an E-Class Mercedes-Benz estate or 5 Series BMW Touring. Either will be less than a year old, but the question I am really stuck on is whether to go for petrol or diesel. I only cover around 10,000 miles a year and, on that basis, was always under the impression that petrol should be the choice as diesel cars are generally more expensive to purchase and service. Also, of course, there is the potential for problems with the DPF on regular shorter runs. The salesmen, however, all seem to suggest the diesel version and I would therefore very much appreciate your impartial view.

Asked on 28 April 2012 by BB, Tunbridge Wells

Answered by Honest John
If you can get it written into the purchase contract that you will never have any DPF problems, then go for the diesel. If you can't, go for a petrol engine. More than 50 per cent of new cars sold in the UK are now diesels, but 90 per cent of those are sold onto fleets that dispose of them at around three years old before the big trouble starts. The problem is that if the Great British Public starts to realise they are buying dud ex-fleet cars, the values of all used diesels will plummet. BMW DPFs tend to last 80,000 – 120,000 miles, then cost between £1000 and £2000 to replace.
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