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Mazda 6 Tourer - Petrol or Diesel - Man without a plan

Hi folks,

I'm currently in the market for a family estate with the little'uns growing up and needing more leg room. The Mazda6 tourer caught my eye and they have some great offers on brand new at the moment - top of the range Sport Nav model <£25k (when factoring in dealers deposit contribution) and 0% for 3 years.

Anyway my conundrum is the age old Petrol or Diesel but i'm aware its a changing landscape so knew I couldn't necessarily rely on old advice on the same topic.

So anyway, I drive approximately 15,000 miles per year. I'm looking to buy the car new and keep for 10 years odd. The difference in purchase price is C.£2000 between diesel and petrol. The road tax is the same on both.

Based on HJs Real MPG it suggests 39.1MPG in the petrol or 48.9MPG in the diesel. That equates to about £400 per year less fuel cost in the diesel at current rates. Thats £4000 over 10 years minus the £2k purchase price difference = £2k overall. (Appreciate all of this is a bit speculative)

Residuals after 10 years are likely to be negligible?

So my question is, would people recommend going for the petrol or the diesel based on the above plus maintenance/servicing of the respective engines and the current climate that may involve future punative charges on diesels?

Mazda 6 Tourer - Petrol or Diesel - csgmart

I'm far from an expert but personally for only £2k difference I'd stick with petrol - less parts to go wrong and Mazda don't have a great reputation when it comes to diesel engines.

EDIT: Aside from this advice I would also encourage you to try some brokers to get the best price for your new car. The discounts can be quite substantial. Try Carwow, Drive the Deal and Carfile. Not associated with any of these but have used them all to get very competitive quotes. You can then go to your local dealer and ask if they will match or better the price.

Edited by csgmart on 16/08/2017 at 17:41

Mazda 6 Tourer - Petrol or Diesel - kiss (keep it simple)

Is the diesel a belt cam? If so, you will be looking at at least a couple of changes in 10 years. Also DPF and DMF are not likely to last that long, so that 2k saving could be swallowed up easily.

Mazda 6 Tourer - Petrol or Diesel - Avant
I'd say petrol every time. Mazda may have sorted the problems with their diesel engines, but the newer ones haven't been around long enough for us to know.

If fuel consumption is a worry, consider a Skoda Octavia estate with the 1.4 TSI engine: this should gib you economy almost up to the level of the diesel Mazda .
Mazda 6 Tourer - Petrol or Diesel - SLO76
The Mazda 2.2 Skyactiv-D has developed a rather nasty reputation for fragility which removes it from contention in my opinion. The petrol despite being much slower is pretty much vice free and should if looked after properly prove utterly reliable. It's certainly a car I'd shortlist with this kind of longterm ownership in mind. It's a handsome, pleasant driving big family bus with a relatively simple normally asperated chain cam petrol engine and thus is ideal for you. I'd personally be looking at nearly new rather than new as large petrol engined cars suffer heavy depreciation in the first few years. A quick look around and there's a few 2.0 SE models with nav around £17k with delivery mileage.
I'd also take a look at the Skoda Superb 1.4 TSi 150PS which is huge inside, better on fuel and quicker but the jury is still out on the longterm durability of VW's TSi engines. To date they're proving robust. If it was my money I'd be in a used Mazda 6.
Mazda 6 Tourer - Petrol or Diesel - Engineer Andy

I would agree that the OP should look at getting the car (Mazda6 I mean) via a broker as well as looking at local low or del mileage discounts - I've regularly seen discounts of around the 20% mark across the Mazda range (except the CX-3) on HJ's 'Cars for Sale' (New) section, and is also a good source of low or del mileage ones as well.

I found that at certain times of the year, primarily just before/after the reg change (imminent) and New Year, that many showroom and ex-demos with well under 1000 miles (many under 100) are going for a song in Mazda dealerships. I almost went for a Mazda3 2.0 Sport Nav Fastback last year that was up for (if I recall) around the £16k mark (before haggling) or so with that sort of miles on the clock at my local dealership, list price of £20.8k, roughly matching the brokers but ready to go (no X month wait). Saw some top-of-the-range 6s for under £20k at the same time. Gone within a couple of weeks.

Might be worth the OP take a trip to some local dealerships after looking around on the websites for offers at these times.

Mazda 6 Tourer - Petrol or Diesel - Man without a plan

Thanks for the comments so far guys. Don't worry, I'm a big fan of Drive The Deal - purchased a brand new fiesta from them and it's now ten years old and approaching 100k.

Mazda 6 Tourer - Petrol or Diesel - Terry W

With current nervousness over diesel, to shift excess diesels the price may be reduced to match petrols for which demand is increasing.

On your current figues I would go for petrol. It will take 5 years to recover the extra cost. In 5 years there is a risk that the value of diesels will take a big hit due to regulatory changes.

If you keep the car for 10 years, petrol will still have some value, but diesel may be scrap due to new or expected regulation - barred from many major cities a premium tax is placed on diesels. additional fuel taxes, additional road tax etc.

This is of course all speculation - we don't know what will happen but simply make a decision on our best assessment of what we know today. The savings by using diesel fuel are just too small to justify the risks to resale value at either the 5 or 10 year timescales

Mazda 6 Tourer - Petrol or Diesel - Engineer Andy

Not just that, as if the owner has a reasonable period of time doing shorter journeys where the auto DPF regen cannot operate when it wants, it will clog up and cost a lot to fix, adding to the running costs, especially if it needs a new one rather than just a forced regen at the dealership or professional clean at a specialist.

Cars with DPFs would work so much better/be more reliable if the driver gets a countdown warning (days) to when a regen is due (and an estimate of how long to run the car as per the maunal to facilitate it) so the owner can at least go out for a blast for 15-20 mins down the motorway etc when required, maybe even having a button to force it early on such a route when its more convenient (this was suggested by Aussie car reviewer/critic John Cadogan - he doesn't mince his words when he speaks!).

Given most second hand buyers don't know how a diesel was driven before they got it (unless it has really higher mileage on it and only one owner), they are essentially throwing dice when buying for the state of the engine and DPF in particular. As more people realise this, as well as throught the dieselgate scandal and politicians mooting banning older diesel cars in cities, second-hand prices will inevitably come down compared to petrols (which may actually stablise or go up for a while as demand increases).