Mazda CX-5 - Mazda CX-5 - Petrol vs Diesel 2WD - mwahahaha

Hi Everyone.

We are looking at the Mazda CX-5 currently as a family car.

I'm looking at the engine options- 2.0L 165HP Petrol vs 2.2 150HP Diesel (Both 2 wheel drive) I'm unsure about which engine option will suit us best and would welcome any input the community has. Here's some info around our useage-

- This will be a long term purchase, not a change after 3 years (DPF's and DMF's scare me on the diesel once it drops out of warranty.)

- It won't do more that 10k miles per year

- The car will cover more stop/start A-road driving than motorway (Motorwary will just be on family trips at weekends)

One on hand the diesel has some nice grunt low down in the range so you're not changing gear all the time and the turbo gives you good power when you need it. On the other hand I worry that a Euro6 diesel will give me some scary bills in 4-5 years that a 4 cylinder naturally aspirated petrol has more chance of avoiding.

On the other hand the diesel is cheaper on road tax and gets better MPG on a long run. But this would be wiped out by the cheaper purchase price of the petrol and lower fuel cost per litre.

Any words of advice from anyone greatly appreciated!

Thanks, Dan.

Mazda CX-5 - Mazda CX-5 - Petrol vs Diesel 2WD - RobJP

I'd be very dubious about any Mazda at all. There is a history of oil filter blockage problems, and engine failures resulting from these. A few threads on here, do a bit of research to see.

Mazda CX-5 - Mazda CX-5 - Petrol vs Diesel 2WD - mwahahaha

I've read some of the long thread re: diesel appearing in the oil which sounds exactly like the kind of issue that worries me about diesels.

I've had BMW diesels for nearly 4 years now as company cars and never had a single issue, as soon as I buy one however it'll be a nightmare I'm sure lol!

Mazda CX-5 - Mazda CX-5 - Petrol vs Diesel 2WD - RobJP

With Mazdas, it isnt diesel in the oil (though that can happen), as much as there is a second oil filter - almost a fibre one - built into the bottom of the engine by the oil pump area. These, it seems, aren't changed at servicing, so eventually they get blocked up, and the engine fails catastrophically on the spot.

Much like you, I run a BMW diesel - personally owned in my case though (a 'new-shape' 325d estate). I've run BMWs as personal cars for the last decade or more, doing 15-25k a year, and I've had 1 problem in that time, an electronic control module for the auto lights.

The biggest problem with BMWs is that the official oil change interval really isn't good enough, usually coming at every 20k miles or so. I used to work in oil development and testing, and the amount of degradation in oils after that amount of miles will be horrific. Might work in the short term, but after a few years, you get those horrible timing chain failures. The best solution to that is simply to ensure that the oil and filter get changed every 10k instead.

Mazda CX-5 - Mazda CX-5 - Petrol vs Diesel 2WD - Happy Blue!

If you are looking at the Mazda CX-5, you may find the new shape Nissan Qashqai with its new diesel engine to be more suited to you. HJ suggests that it is unlikely to suffer the problems which low mileage and stop start driving can cause.

Mazda CX-5 - Mazda CX-5 - Petrol vs Diesel 2WD - Alby Back
I'd be looking at that option too HB. In fact we are looking at it for 'her' next car maybe.
Mazda CX-5 - Mazda CX-5 - Petrol vs Diesel 2WD - groaver

Nothing in life is certain (other than death and taxes). If you are set on the good looking Mazda I would feel more comfortable driving the petrol one and with your mileage it's unlikely that you will save money on fuel anyway over its lifetime.

I do like mazda' s approach to make larger engines more economical rather than putting a small one on steroids.

Mazda CX-5 - Mazda CX-5 - Petrol vs Diesel 2WD - mwahahaha

Hi everyone, thank you for the replies.

RobJP - Mine have both been the 2l x18d - I had a 118d sport 5 door and now a 318d msport saloon which have both been mechanically faultless other than a misaligned boot lid on the 3 series which got done under warranty. When I read all these threads about DPF regeneration I haven't seen any of those symptoms and being a lease car I don't exaclty look after it other than take it in when a service warning comes on.

Happy Blue and Alby Back, thans for the Quasqai recommendation, I do really like the look of the new one, big improvement IMHO. The reason for the Mazda as a preference is that I can get a significant amount off list price as a family member works for them, so it would be the CX-5 as a new car or another brand/model from the used market.

Grover - yes me too, the petrol not being something like a 1.6 turbo is quite appealing - I was saying to someone at work the other day there will be a massive market for turbocharger rebuilds and replacements in a few years time when all these forced induction small engines start having boost issues...

I need to go and test drive the petrol, I've driven a few of the CX-5 diesels but not the petrol so that will of course be a big deciding factor. I'm just waiting on getting my next lease car sorted as part of the plan is to drop my BIK/Company Car Tax in order to free up some funds towards the payments on this rather than to the tax man.

Mazda CX-5 - Mazda CX-5 - Petrol vs Diesel 2WD - xtrailman

I tow a caravan so torque is top of my list, i bought the 175ps diesel which is briiliant to drive.

The petrol car had zero appeal to me as it has no turbo, i've towed with both petrol and diesel, and fitted with a turbo make great cars both solo and towing.

Mazda also do a 2.5L petrol in the USA.

But your requirements are different, a if youre happy with a less complex petrol engine then go for it.

Never had a failed DPF, or DMF so can't comment.

I am coming up to my 1 year service this month with under 7K miles clocked up, very little high speed motorway, mainly local driving in the Worksop area, in car computer shows around 44mpg locally, most i've had on a A,B road run is over 55mpg.

Not great, but not bad either with upto 420nm of torque.

Yes i have some oil rise, same as with the xtrail diesel, but only around 8mm over the full mark, so not an issue with my low milage.

As for BMW in the long term, my son had a campact petrol, which he really liked to drive, but at 60K the timing chain failed, resulting in a £900 repair, cam shaft sensor failed twice at a cost to replace of around £80 each, so in the end he traded it for a Astra petrol.

I have found the Nissan very reliable, my last one was 100% reliable fitted with the 173ps Renault engine, used over 4.5 years.


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