Why Mazda did so well and Volvo so poorly in Consumer Reports survey

The poor performances of Tesla and all three domestic automakers got the headlines in Consumer Reports magazine's latest reliability survey, but there were other results that caught our interest.

Tiny Mazda notched the biggest gain among the 29 brands included in this year's list, leap-frogging nine spots to No. 3. Buick, which was in the top 10 last year, fell 11 spots to No. 19, the biggest decline of any brand. And then there's Volvo, a brand often vaunted for its quality and reliability, dropping six spots to dead last. What gives?

For starters, all three brands benefited or suffered in large part due to their relatively small portfolio of vehicles. So when raves or complaints rolled in for even one particular model, as was often the case, it weighed heavily on the entire brand. That's especially true when it involves a relatively high-volume, hot-selling model such as the Buick Enclave (more on that in a moment).

Mazda fared as well as it did despite the CX-3 losing Consumer Reports' influential "recommended" status due to problems with its climate system, including leaks from the condenser and refrigerant unit that triggered a service bulletin from the automaker in late 2016. Deputy auto editor Jon Linkov said that scratch didn't hurt the overall brand, since the CX-9 crossover and MX-5 Miata both jumped up to replace it on CR's list of newly recommended vehicles, thanks to several back fixes Mazda made to both models.

For Buick, the redesigned Enclave SUV earned a "Much Worse Than Average" rating after owners reported problems with the new nine-speed automatic transmission it shares with the Chevrolet Traverse as well as some issues with the climate system. There were issues with rough shifting, plus complaints about the torque converter that necessitated fixes to the computer or outright replacement. "Again, similar stuff that we saw with the Traverse: both first-year vehicles, similar powertrains," LInkov said.

He said all-new vehicles or redesigns typically fare poorly in CR's reliability survey due to issues that are hard to suss out before vehicles go into everyday use by consumers. The top-selling Encore and Envision fared well, Linkov said, but were outdone by the Enclave's problematic transmission components. The Enclave was Buick's second best-selling model through September at 35,227 units.

Then there is Volvo, about which there is one word to sum up its woes: infotainment. Specifically, the new infotainment system shared by the XC60 and XC90 crossovers and S90 sedan. But with so much tied to the technology — it controls everything from heating and cooling, to navigation and entertainment — when it goes wrong, it can render the vehicle nearly unusable. Think of a car you can't heat during the dead of winter, for instance. Owners of the XC90 also reported some issues with engine computer problems, exhaust leaks and harsh shifting from the transmission, Linkov said. "They have so many new systems that there's a lot going on that they need to work out," he said.