Mazda 6 - 2018 facelift diesel reliability | Motoring discussion | Back Room Forum

Fri 3 Aug 2018 08:23

Mazda 6 - 2018 facelift diesel reliability - Opposition

Hi,

I am looking to be buying the new Mazda 6 2018 facelift model.

I am unsure which engine to choose, but I have narrowed down my options to the 2.5 (194ps) petrol engine and the 2.2 (184ps) diesel engine. I drive a little more than 31.000 miles annually, due to my job, where 80% of the drive is on the motorway.

I have read that the Mazda diesel engines are not so reliable. Having problems such as cam chain snapping off, DPF issues, clogged oil strainer, oil dilution and a few more.

The reason why I still contemplate the diesel engine is, that the 2.5 seems rather low on torque. I have driven cars low on torque before, namely the 1.3 99ps Honda Jazz. You'll have to rev the nutts of it, every time, in order to overtake on the motorway or accelerate after a stop light. It was nice and engaging the first few months, but it is just feeling like an extra chore now, rather than providing a relaxing commute journey.

Has the diesel problems been addressed by Mazda? Having only one car, the reliability is an important factor for me.

However, I did see in the brochure, that the facelifted diesel engine has been increased from 175ps to 184ps and the compression has been increased by a fraction. So I guess some modifications has been done to the engine. I just hope reliability was one of them.

Edited by Opposition on 03/08/2018 at 08:32

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Fri 3 Aug 2018 09:45

Mazda 6 - 2018 facelift diesel reliability - gordonbennet

If you are keeping the car for as long the warranty period only, then in some ways it doesn't matter too much if the engine does suffer from one of the above problems, chances are it won't and if it does then it's likely to be one isolated incident.

Where this changes is where you intend to keep the car long term after warranty has expired, and this is where some makers don't earn themselves a great reputation for standing by their product or customer when things go wrong.

Your motoring is ideal for a Diesel.

World of difference between a 1.3 NA and 2.5 turbocharged petrol engine, Mazda petrol engines are almost never discussed regarding failures.

What are the torque figures and do you have a graph or some idea of the rev bands where that torque can be found, my experience of larger petrol engines (a 2.5 4 pot has decent swept volume per cyl) with forced intake is that they take off like a scalded cat and just keep going.

At 194 the power is fairly low for a turbocharged 2.5, i suspect that is one of the reasons for their renowned reliability (Hyundais seem to be like this, keeping the power down for a long engine life) and probably why the fuel penalty won't be as bad as it could...try a 2.5T Subaru if you want to see how quickly a turbo petrol tuned for power can get through fuel!

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Fri 3 Aug 2018 10:26

Mazda 6 - 2018 facelift diesel reliability - Opposition

The Mazda 2.5 is NA for the European market, unfortunately.

It will have around 258nm of torque as opposed to the 445nm on the diesel version. That is why I think the difference might be significant for daily drive.

I don't have access to graphs but the 2.5 seems to be doing 258nm at 4000 rpm while the 2.2 is doing 445nm at 2000 rpm.

The warranty will expire after 2 years due to my high milage, since Mazda only offers 100.000km / 3 years in my country.

Preferably I would like to swap to their Skyactiv-X platform, when it is available for the Mazda 6. But that is most likely 3-4 years away from now. I will maybe even wait another 1-2 year after the launch, to avoid the initial problems related to a newly released platform.

That means that I am looking at keeping this car for 5-6 years, where the warranty already expires after the first 2 years.

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Fri 3 Aug 2018 10:45

Mazda 6 - 2018 facelift diesel reliability - gordonbennet

I am mistaken, i assumed the 2.5 would be turbocharged.

In that case i too would not want the petrol engine if its NA, and bearing in mind your mileage and how quickly the car would be out of warranty and keeping in mind what i have read and heard of Mazda's version of customer service, it would be a risk too far for me to go for the Diesel, despite the Mazdas handsome look.

You mention another country, in the UK Hyundai's warranty is the best in the business, and i suspect a new i40 is due shortly, Kia's not so good a warranty for high milers but that might not be the case where you live, Optima has to be one of the best looking and competent cars in its class.

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Fri 3 Aug 2018 11:50

Mazda 6 - 2018 facelift diesel reliability - Opposition

I did consider the Kia Optima. Kia has 7 years / 150.000km here, so it will yield me another year of warranty relative to Mazda.

However, I have read that the build quality on Kia Optima is really poor considering the retail price.

It seems that Hyundai has 5 years / unlimited km here. I have not really considered them before. I will take a look at the i40, thanks!

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Fri 3 Aug 2018 15:38

Mazda 6 - 2018 facelift diesel reliability - Falkirk Bairn

31k per year is a lot

Friend of a friend did similar mileages.

Depreciation is a killer with these mileages.

He bough 18 mth/2 yr old low mileage car with say 12K miles - sold after 12 months or so with 40K+/- Just above average & still sellable at a good price. He reckoned it cheaper than buying new & having high deprciation & a car with 90K to sell after 3 years.

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Fri 3 Aug 2018 15:43

Mazda 6 - 2018 facelift diesel reliability - TheGentlemanThug

The 2.5 seems like an odd choice given the mileage and type of driving you do. Given how new the car will be, reliability shouldn't be much of a concern, so I wouldn't hesitate to go for the diesel.

Depreciation is going to be the largest expense by far, so you may want to consider a pre-facelift model to help offset some of the cost.

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Fri 3 Aug 2018 17:23

Mazda 6 - 2018 facelift diesel reliability - SLO76

Only time will tell if Mazda have finally sorted the issues with this particular engine but they haven’t the best reputation for diesels in recent years and they’ve made it clear that they plan on pushing development money into petrol rather than diesel from now on so I’m not overly confident in the 2.2 Skyactiv diesels despite being a fan of the marque and the model.

Doing heavy mileage like this i’d sooner buy a 2-4yr old mass market diesel hatch like a Mondeo 2.0, Hyundai i40 5yr unlimited mileage warranty if it has a full dealer history) or possibly a Toyota Avensis though the later diesels are BMW units which can be troublesome if not looked after meticulously. A size down would present the Honda Civic 1.6 DTEC which will do big six figure mileages and still sell for decent money plus its free to tax and will do a genuine 70mpg on a run. This is probably where my money would go for such a heavy mileage instead of spending much more on a car that will plummet in value with 30k plus added every year.

Edited by SLO76 on 03/08/2018 at 17:24

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