The semi-annual meeting of the General Motors Law Enforcement Product Council (LEPC) was held in conjunction with the COPS West convention and the Los Angeles County Sheriff police vehicle tests. The LEPC is made up of U.S. and Canadian police fleet managers and GM Fleet service, technical, sales and engineering personnel.
Twice a year, the LEPC meets for a two-way dialog, i.e., fleet managers tell GM Fleet what they need to hear, and vice versa. This is also a time for sounding out ideas from proposed improvements to the next model car to design parameters for the next generation car.
The opening news was the successful retest of the 2006 Impala brakes by the Michigan State Police. After a change to the ABS calibration software, the Impala stopped in an acceptable 142.5 feet, comparable to the Ford CVPI.
A discussion was held on fuel economy, of course, and the results are mixed, of course. The Peel Regional Police in Ontario, Canada, compared the fuel economy of their Ford CVPIs to their Chevy Impalas. Both are used for the same kind of calls for service and general patrol. They found, on the average, the Impala got 2.5 mpg better mileage. This difference was also experienced by the Illinois State Police with their urban-driven Impalas.
However, the North Carolina Highway Patrol compared the fuel economy for their most active troopers and reached a different conclusion. In comparing 25 CVPIs and 25 Impalas on high activity, aggressive troopers, the average mileage for each vehicle was the same. Neither vehicle had an economy edge over the other, i.e., the troopers with the Impalas really put their foot into the car.
On the topic of fuel economy, fuel prices and alternative fuels, while the Tahoe is available in flexible fuel or E85, the police package Impala is not. A retail version of the Impala is available as an E85 (85% ethanol, 15% gasoline). However, this is only on the 211 hp, 3.5L V-6 and not the police spec 240 hp, 3.9L V-6. Of course, the retail Impala has none of the heavy-duty police components.
A good deal of time was spent in a hands-on workshop to develop a universal cargo box for the Tahoe. The way to lower the cost of these cargo boxes is to increase the volume. Instead of different fabricators making 10 custom-made units for 100 different police departments, there would be one, standardized high-volume box.
The key is to make the standard box as versatile and task flexible as possible. Numerous versions were discussed, and valuable input came from Kerr Industries
(the GM Fleet factory upfitter), the Texas Highway Patrol and the New York State Police.
This is an ongoing project that will continue at the next LEPC meeting. The goal is to combine the needs of commercial enforcement, tactical teams, supervisors, command & control, and routine patrol into one basic design. The target price is $650 and the market is expected to include 90% of the police and special service SUVs, along with a number of vans and pickup trucks.New Cars
The new police package Impala went into production around Thanksgiving. A slight running change to the police package Impala is the interior trim. The high gloss, wood grain trim on the console, dash and door panels is changing to brushed metallic aluminum. This really is intended to make the police Impala less fancy in appearance and more business-like.
Production of the current generation Tahoe ended in late October. Production of the next generation pursuit-rated Tahoe will not start until November 2006 as a 2007 model. The new Tahoe will have a wider track, more horsepower, no roof rack and a 17-inch brake, wheel and tire system. The electrical system will be virtually identical to the Impala.
The side curtain airbag remains a challenge for police departments using a B-pillar mounted prisoner partition. The New York Police Department reported favorable initial results with the Setina unit, which is relieved for the side curtain deployment. While the gap allows hand contact between the prisoner and the driver, the assumption is that prisoners will be handcuffed.Pirelli Tires
The 2006 Impala comes with Pirelli P6 Four Seasons V-rated tires. Pirelli
is a new name to many police fleet managers. To smooth the transition to Pirelli tires, especially for replacement tires, GM Fleet and Pirelli have done some homework.
Pirelli will handle state bids and GSA bids, and they will also do stand-alone contracts for cities and counties. They will ship factory-direct to 1) a police central distribution warehouse, 2) a local Pirelli dealer, 3) a regional Pirelli warehouse, and 4) direct to the police garage, post or barracks. With a police account, they will guarantee shipment of the police tire to whatever location within 36 hours.Service Issues
The legendary Earl Gautsche covered recent service issues with the Impala. First, the warranty for the catalytic converter on the 2000 to 2002 model Impalas has been extended from eight years and 80K miles to 10 years and 120K miles. The catalytic converter design was changed for the 2003 model year.
The new GM Oil Life System is starting to be followed by police departments. Per the Owner’s Manual, do not change the engine oil at 3,000 miles. Instead, wait until the “Change Engine Oil” light on the dash illuminates. Police departments are already reporting oil change intervals (on marked patrol units) being extended up to 6,000 miles. The GM engine warranty is based on the Oil Life System. Changing the oil more frequently than the OLS indicates is NOT necessary.
Gautsche also explained two very unique features on the Impala 3.9L V-6; engine features, which explain the Impala’s 142 mph top speed. First, the 3.9L engine has Variable Valve Timing, a first for a cam-in-block, pushrod engine. With this system, the camshaft is rotated between 15 degrees advanced and 45 degrees retarded, depending on engine demands.
Second, the V-6 engine also uses a dual air intake. At low engine speeds, a manifold valve closes to force air inlet through a “long loop” intake path for maximum bottom end torque. At high engine rpms, the manifold valve opens and the intake air travels through a “short loop” for maximum top end horsepower. This is a drag racing trick that dates back to the late 1950s!Top Speed
The last service issue was a clarification of top speed, and a debunking of a lot of misunderstandings. On the 2000 to 2005 Impalas, the speedometer goes to 140 mph, the speed limiter shuts off at 129 mph, and the Michigan State Police tests record 124 mph. So, what top speed should be expected?
First, the MSP tests are run on slicktop cars with no spotlights and no police equipment. Once in-service, with 250 pounds in the trunk, a 250-pound passenger, and 200 pounds of communications gear, pusher bumper and partition cage, it is reasonable to think the top speed would go down and the acceleration times will go up. Now add a lightbar (of any design) and twin spotlights and the top speed takes another dip down. For the 2000 to 2005 model years, the lightly loaded, slicktop Impalas will indeed reach the mid-120s. Heavily loaded, fully marked and equipped cars may indeed only get to between 112 and 118 mph.
On the topic of realism, a significant discussion was held on realistic vehicle testing including the concept of a “police” load in the test vehicle. Such a load may be an 80- to 100-pound ballast on the front end (pusher bar), a 200- to 250-pound ballast near the passenger seat (two-officer unit), and a 250- to 400-pound ballast in the trunk.
This would revolutionize police vehicle testing and make the results much more realistic. Such ballast dramatically changes the handling of most police package vehicles. Of course, it affects the acceleration and deceleration rates of all vehicles.
Such a change would obviously involve the two major testing departments, Los Angeles County Sheriff and Michigan State Police, and will also involve all three police car manufacturers. But it is the right direction to go.Special Service Work Truck
No gathering of police fleet managers is complete without a discussion of a non-pursuit, special service package pickup truck. A need exists for a 4x4, four-door, column shift, 1/2-ton or 3/4-ton pickup. This is basically a rubber floor-matted work truck with a big alternator, no center console, and no inside overhead gadgets.
Short on time in late 2005, this will be the topic of an extended workshop during the April 2006 LEPC meeting. Let GM Fleet, the LEPC board members or the editor of PFM
know your thoughts on such a police truck.