Edmunds accuses Ford of tricky tire-switching with their Lincoln MKZ test car

Automakers routinely loan vehicles to media outlets for evaluation, leaving magazines, newspapers, and websites trusting that the cars are production representative. It turns out, so-called press cars can vary, as can their test results.

Auto-information site Edmunds.com recently found that a borrowed 2013 Lincoln MKZ AWD was equipped with high-performance tires and accused the company of gaming the media with their test car. The fitted Michelin Pilot Super Sport summer tires (245/40ZR19) are more typically found on super-expensive exotica like the BMW M5 and Ferrari 599, not $45,000 luxury sedans.

With those tires, rather than the standard, efficiency-biased Michelin Primacy MXM4 (245/45R18) tires, the MKZ went through their slalom just 1 mph slower than a Porsche 911 and quicker than a BMW M5.

The implication was that these were special tires fitted to the test car. Ford verified to Consumer Reports that these tires are part of a 19-inch summer handling package available on AWD and Hybrid models. Priced at $1,565, the package includes sport-tuned suspension and steering, along with the larger wheels and tires. Ford would not speculate on the take rate, but we anticipate this being a relatively rare combination. (Most AWD sedan customers are looking for traction and convenience, not seasonal tire changes at a significant cost. Likewise, Hybrid buyers are not likely to pay extra for tires that will probably reduce efficiency.) The LA Times reported being told by a Ford spokesperson that fewer than 1 percent of customers will choose that option, supporting our view.

Fortunately, super-sticky tires are easy to spot, and in this case, they are a legitimate factory option. But what if a manufacturer tries to trick the media? It's not hard to tweak spring rates and shocks, crank up turbocharger boost, or add in some more noise insulation. Such discrete modifications may have been omitted on production models due to cost, fuel economy, or reliability—concerns that don't matter much in the short life of a press fleet car whose job is to make a positive impression on the media and its readership. Further, it is not uncommon for press cars to be configured in a way that is most likely to shine in instrumented testing, rather than to reflect how most models will be sold.

We have experienced cars from manufacturers that perform better than the vehicles that we end up purchasing to test. Even government agencies are not exempt from this practice, as car manufacturers select vehicles that they test themselves in the EPA fuel economy tests.

This is why at Consumer Reports we buy every product that we test. While we do tell you our first impressions of press cars before they go on sale (we pay to rent them), we only formally test and score cars that we purchase anonymously.

We commend Edmunds for highlighting this. We look forward to buying a more representative example of the Lincoln MKZ, just like the one consumers will, to see how it fares in our full battery of tests.

Learn how we test cars.

Updated: 12/18/19, clarifying tire availability.

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