Mazda made no secret it would unveil an all-new CX-5 compact crossover—now one of its best-selling models in the U.S.—at the 2016 Los Angeles auto show. The surprise Mazda saved for the day after the 2017 CX-5’s introduction was that the new CX-5 will offer a diesel-engine option for the North American market.
It will be Mazda’s first-ever U.S.-market diesel when it goes on sale in the second half of 2017.
Big torque, less clatter
The company did not provide specifications for the Skyactiv-D 2.2.-L four cylinder slated for the U.S.-specification CX-5, but Akira Marumoto, Mazda executive vice president, promised it will “have the torque of an engine almost twice its size,” while delivering “fuel efficiency at the hybrid level.”
Mazda sources told Automotive Engineering the diesel engine is a new architecture designed from the outset to be coupled with selective catalytic reduction (SCR) exhaust aftertreatment. The current Skyactive diesel engine family—used extensively in Japan and once earmarked for U.S.-market vehicles such as the Mazda6 sedan—does not employ SCR technology. The lack of SCR likely is what caused Mazda to suspend its initial plans for deployment of the diesel in the U.S., and in wake of the Volkswagen diesel-emissions scandal that also centered largely on VW’s desire to use diesels without costly SCR technology, hindsight might indicate Mazda was wise not to deploy its non-SCR diesel in the U.S.
At the Los Angeles auto show unveiling of the 2017 CX-5 and announcement of the new diesel-engine availability, Marumoto admitted that developing a diesel to reliably comply with U.S. emissions standards “took longer than expected,” but added, “I can promise this engine will not disappoint.”
He also said that Mazda has engineered unique technologies for the new, all-aluminum Skyactiv-D engine to damper diesel clatter, dubbing them “Natural Sound Smoother” and “Natural Sound Frequency Control,” without elaborating further. Sources did say, however, that exceptional efficiency and low emissions are expected because of the new engine’s extremely low compression ratio, which is projected to be near or even equal to the company’s gasoline four-cylinder.
The current Skyactiv diesel four-cylinder has a compression ratio of 14:1—Mazda claims it to be the diesel-world’s lowest—while the Skyactiv gasoline four-cylinder used in the 2016 CX-5 crossover has a 13:1 compression ratio. Mazda did not provide any guidance on power or torque for the new 2.2-L Skyactiv-D, but the output of the current Skyactiv diesel might offer useful reference, that engine developing a listed 173 hp (129 kW) and 310 lb·ft (420 N·m).
The company further promised the 2.2-L Skyactiv-D will uphold Mazda’s reputation for engaging driving characteristics thanks to its high torque output and a focus on revving willingly to high rpm.
The new 2017 CX-5 seems an ideal candidate for Mazda’s first-ever diesel: its styling is husky and assertive, with a grille that closely mimics the recently launched CX-9 large crossover. The new crossover’s interior also appears upgraded and more substantial, and the company promised improved interior quietness and refinement.
In size, however, the 2017 CX-5 closely mimics the current model. The 106.3-in (2700-mm) wheelbase is the same, and the 2017 model’s 179.1-in (4549-mm) overall length and 72.5-in (1842-mm) width are within a couple tenths of the current CX-5. Mazda did not yet list curb weights for the 2017 CX-5 lineup, but the current model in top-trim all-wheel-drive form weighs 3589 lb (1628 kg).
Mazda said the new CX-5 has an increase in torsional rigidity of 15.5% and there is increased use of ultra-high-tensile steel, including 1180 MPa steel for the A-pillars and 980 MPa steel for the side sills and B-pillars.
The front suspension continues with a MacPherson strut layout, and there is a multilink design for the rear suspension. Mazda is incorporating its recently introduced G-Vectoring Control (http://articles.sae.org/15002) to sharpen corner turn-in characteristics.
The 2017 CX-5 will launch early next year; for now, Mazda indicates the only gasoline engine used will be the 2.5-L Skyactiv-G; the current CX-5 also offers the smaller 2.0-L version of the Skyactiv-G. The company’s early specifications also list only a six-speed automatic transmission as being coupled with the 2.5-L engine. For the diesel-engine launch time frame, company officials would not commit to anything narrower than the second half of 2017 statement.Continue reading »