The hostage negotiator was responding to the scene of a barricaded gunman in his admin police Impala. It was gently raining and, of course, the Impala 9C3 was being driven hard—this was an emergency. On a number of occasions during the run, the tires lost traction on the slippery pavement, even though the police-oriented replacement tires had half the tread remaining.
On one occasion, the negotiator slid ABS-activated through a four-way stop. The little chat with the fleet manager afterward went something like this: “These tires are slippery when wet! Get me tires with better traction!” (True story.) Police Fleet Manager recently teamed up with Tire Rack to conduct wet and dry braking and handling tests of five different police-oriented tires. The overall winner was the Firestone Firehawk GT Pursuit. Parts of this overall win were first-place finishes in the wet road course, the wet static circle, the wet stopping distances and the wet transient response for the Firehawk GT Pursuit.
The Tire Rack customer surveys, posted on its Web site, confirm the relative ranking of the Police Fleet Manager tests. Of the three police-oriented brands of tire for the Impala, the retail Firehawk GT has an 82 percent rating. The Pirelli P6 Four Seasons (OE on the Impala) has a 74 percent rating. The Goodyear Eagle RS-A (OE on the Ford CVPI) has a 66 percent rating. Tire Rack’s survey results were based on a combined 100 million consumer miles driven. These results did not include the police-only Firehawk GT Pursuit.
In discussing these results at the Police Fleet Expo-West, a number of fleet managers in attendance said they did not realize how slippery their OE police-spec tires were until they put Firestone Firehawks on their patrol cars. The Firehawk GT Pursuit is available for the Ford CVPI and the police Dodge Charger.
Police & Admin Impala
But what about the police Impala? Roughly 10,000 Impalas go into police service per year. The police Impala uses a P225/60, 16-inch V-rated tire. The Firehawk GT Pursuit is not available in that size. However, an H-rated (130 mph) Firehawk GT is available in a size to fit the police Impala.
A number of departments, especially in the wet Northwest, are using this retail tire for routine police patrol in addition to admin use. The wet traction is so good, and the need for speeds over 130 in an Impala is so rare, that the retail Firehawk GT has proven a good choice on these police Impalas.
On our test vehicle, we removed the half-worn Goodyear Eagle RS-A and put on the retail Firestone Firehawk GT. We put 14,000 miles on the Firehawk GT during one of the wettest summers in years, through the heat of fall and the light snow of an early Midwest winter.
The improvement in wet traction was immediately obvious. During acceleration from a stop, cornering at urban and suburban speeds, and braking on a variety of wet road surfaces, the Firehawk GT had more wet traction. The resistance to hydroplane, with apples-to-apples tread depth, was also much better with the Firehawk GT.
On hot, dry pavement, we could not tell any difference between the Firehawk GT and other police tires. The cornering stability; dry traction during acceleration, braking and cornering; and steering response were all about the same. Under dry conditions during police admin use, including occasional emergency driving, the Firehawk GT performed fine.
All police package vehicles come with “high performance all-season” tires. As such, all these are, at best, only “good” on cold winter pavement, light and heavy snow, packed snow and ice. However, most police departments run all-season tires during the winter snow, so some assessment has to be made as to whether or not the tire was designed for such service.
In light snow, the Firehawk GT seemed to perform better than other police tires—perhaps a “good” for the Firehawk GT and a “fair” for the other two police tires. Under winter road conditions of heavier snow, packed snow and ice, it was impossible to discern any difference with the Firehawk GT. However, once the snow became slush or water, the Firehawk GT showed its superiority.
Tread wear is such a hot button issue, and it varies so widely from department to department, and even from officer to officer, that the tire life from any one test doesn’t carry much weight. That said, the Eagle RS-As on this particular Impala were halfway to the wear bars at 11,700 miles. The Firehawk GT reached the halfway point at 14,000 miles. That is a 20 percent improvement. You have to run the tread life test in your own department for the comparison to be valid for you. Expect slightly better tread wear.
Retail vs. Pursuit
The Firehawk GT is an asymmetric tread tire. That means a specific sidewall must be mounted to the outside. The tread pattern on the outside of the tire is different from the tread pattern on the inside of the contact patch. The outside has larger shoulder blocks for better steering response. The inside has angled grooves and more sipes for better wet traction.
What are the differences between the H-rated (130 mph) Firehawk GT and the V-rated (149 mph) Firehawk GT Pursuit? First, the non-pursuit Firehawk GT has a 0-degree biased body ply. The Firehawk GT Pursuit has a 5-degree biased body ply. This higher degree of body ply bias allows for better handling and high-speed stability.
The Firehawk GT Pursuit also has some proprietary construction and mold features necessary to meet the higher speed rating. However, the retail Firehawk GT and the Firehawk GT Pursuit have the same tread “pattern.” And the two tires have the same tread “compound.”
In this long-term test on an admin Impala, the Firehawk GT had much better wet performance, the same dry performance, possibly better winter performance and better tread life. The high-speed stability of the H-rated Firehawk was comparable to other police-spec tires with higher speed ratings.
Whether your department’s Impala is used for police patrol or by police negotiators rushing across the county, you should at least try a set of Firestone Firehawk GT tires on the Impala. Based on our long-term test, the retail Firehawk GT is a solid solution to wet performance issues on the police or admin Impala. These tires are definitely not “slippery when wet.”