This is an unusual story – a new diesel motor, not unusual in that it is a new idea, just simply because for most of the world, diesel is a dirty word, especially in many Government departments. However Mazda has bucked the green thinking and delivered a new SkyActiv-D 2.2 litre diesel engine into the US market.
Fitted into a revised CX-5 Signature, the motor has been described as such: it “addresses the strong demand for a diesel engine in the U.S. that offers a premium driving experience.” Being fitted to a vehicle with a high level trim might limit sales, however the CX-5 in general is actually a sales winner for Mazda in this market. They hope that more people will buy a high spec car with a diesel engine – in a market not generally in love with diesel vehicles outside of the large truck market.
The selling point is that the new engine produces far less emissions than earlier versions of the motor and is 15% more fuel efficient that one of their comparable petrol powered engines. Both the diesel and petrol engines are four cylinder turbocharged units of a similar size and the market has questioned whether anyone wants a diesel, especially when fitted to a high trim model – Mazda has also said that the engine will also be fitted into a Mazda 6 saloon and they are working with various States in the US to prove that the emissions meet those States regulations.
That’s also an interesting point, The Mazda engine already complies with Euro6 in Europe and the PNLTR (Post New Long-Term Regulations) in Japan so you would think that minimal work would be needed to gain State and Federal compliance, however all that work to have the engine compliance must cost a chunk of change – is it really worth doing this when most non-US manufacturers are pushing a future of hybrids or full electric powered vehicles. Even Ford and GM have very public plans to deliver electric vehicles whilst abandoning the tradition market segments they dominated for decades.
The key to this new engine is the much lower compression ratio than other diesel engines combined with a two-stage turbocharger. What the engineers have done is to create an engine that doesn’t require any additive such as nitrogen oxides to reduce the emissions. Most manufacturers use an Adblue additive to help reduce the emissions and there is a grumble from many owners that this is an expensive item to refill and in some cases needs to be done only by a dealer. If the vehicle runs outs of the additive it may well fail to restart which in the UK meant that the Automobile Association breakdown service answered 20,000 calls for help in 2017 alone.
Mazda have also discussed the benefits of dropping the compression ratio down to 14.0:1 from a typical diesel engine ratio of up to 20.0:1. They say that with a lower compression ratio, they can now use different materials and lighten the motor itself by 25% which also helps the overall efficiency of the vehicle.
Very few established markets are open to new diesel contenders at the moment, however that might change when Governments come under revenue pressure from a loss of excise and tax. It will be politically incorrect to tax electric cars just yet, however we might see a quiet lifting of some proposed bans focused on petrol and diesel vehicles when the manufacturers show that they are genuinely meeting emissions targets – assuming that those targets are not lowered!
We will look out for the sales figures of the CX-5 and Mazda 6 in the US to see how many are actually sold and whether this particular engine has a short life span in this market.