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Charger Tech Training: Service Intervals & Jump-Starts
The police Charger has less scheduled preventative maintenance than other police sedans, but some PM is still required! On a retail vehicle, the preventative maintenance is pretty much fluids, belts and hoses. Except for the oil drain plug and oil filter, retail PM is mostly looking under the hood. This is not the case for police vehicles where the real PM is the under chassis.
It is not just swapping out front pads. Instead, it is everything it takes to haul a 4,000-pound sedan down from literally 150 mph in a straight line without a hint of either brake fade or brake pull. A slight pull when a retail customer puts on the brakes at 60 mph to slow for a turn is one thing. A slight pull when a traffic officer activates the ABS at 120 mph in an evasive maneuver is quite another thing.
The police Charger tech training makes it clear that all these suspension, brake and wheel fasteners are safety critical and that all must be properly torqued. The police vehicle PM is more than just draining engine oil. Nearly all of the chassis components are safety critical, meaning that a failure will endanger lives. That means there is no margin for error. Use a torque wrench for nearly everything.
Pop quiz: What is the tightening torque for the police Charger caliber (adapter) mounting bolts? The answer is 70 lb-ft for the front and 85 lb-ft for the rear. What is the tightening torque for the wheel lug nuts on the police Charger? The answer is 140 lb-ft, which is quite different from the 110 lb-ft the dealership uses on all other Chargers.
What is the tightening torque on the ball joint stud attached to the lower front control arm? It is 50 lb-ft plus an addition 90-degree turn. How about the lower shock mounting bolt? It is 128 lb-ft. Even the ABS wheel speed sensor head screws need to be precisely torqued to 8 lb-ft.
Oil Change Required
Starting in 2008, Chrysler vehicles came out with an “oil change indicator system.” Based on the engine operating conditions, the instrument panel will display either “Oil Change Required” or “Change Oil.” Under police-type use, the indicator message may illuminate as soon as 3,000 miles. However, the service manual also makes it clear that “under no circumstances should oil change intervals exceed 6,000 miles.”
On a well-maintained police Charger, the oil will be checked each time the gasoline tank is filled. Each month the tire pressure will be checked and the tires will be inspected for damage and unusual wear. The battery will be inspected once a month and the terminals will be cleaned and tightened as required. The fluid levels will be checked once a month in the coolant reservoir, master cylinder, power steering and transmission.
Every 6,000 Miles
Every 6,000 miles change the engine oil and filter; rotate and inspect the tires; inspect the brake pads; and inspect the front suspension, tie rod ends and boot seals. Now you know why the North Carolina Highway Patrol, with the nation’s largest fleet of police Chargers, has such firm PM requirements based around 6,000 mile intervals for their Chargers.
Every 30,000 miles, replace the engine air filter. Every 30,000 miles on the 5.7L HEMI V-8 replace the spark plugs. Every 48,000 miles, change the rear axle fluid on the police Charger. Every 60,000 miles change the transmission fluid and filter on the police Charger. Every 100,000 miles, replace the HOAT engine coolant and the accessory drive belt on both the 3.5L V-6 and 5.7L V-8 police engines. Also at 100,000 miles, replace the cam timing belt and the spark plugs on the 3.5L SOHC V-6.
Since improper upfitting frequently runs the battery dead, one of the most common questions is how to jump start the police Charger without throwing a DTC.
First, is this really an upfitting problem? Yes. Left untouched, the Charger automatically shuts of all factory power drains. The police gear, however, often has unseen, parasitic power draws that will run the battery dead overnight. Proper upfitting includes proper amp draw calculation to be sure the alternator can handle the heavy loads from the upfit gear, and some form of battery protection against the small parasitic loads.
Jump-starting the Charger without throwing a DTC simply involves making the right connections to the right locations in the right order. The police Charger has the battery in the trunk under an access cover. However, remote battery terminals are located in the engine compartment specifically for jump-starting.
If you are using a high output boosting device, do not allow the boost voltage to exceed 16 volts. When using another vehicle as a booster, do not allow the vehicles to touch. Turn the ignition OFF in the boosting vehicle.
First, connect the RED jumper cable clamp to the jump-start positive battery post under the Charger hood. Second, connect the other RED jumper cable clamp to the positive terminal of the battery in the booster vehicle. Third, connect the BLACK jumper cable clamp to the negative terminal of the battery in the booster vehicle. Fourth, connect the other BLACK jumper cable clamp to a suitable engine ground under the hood of the Charger.
This last connection, if clamped to an improper ground in the Charger, is what throws the DTCs. For example, clamping onto a metal HVAC line may be a ground, and may even be enough of a ground to start the car, but the Body Electrical System will sense current where there is not supposed to be any.
One of the suspension bolts in the shock tower is probably a ground, but not the best engine ground. Neither is clamping onto the alternator housing, the radiator or any of the brackets or sub-frame members or any of the fuel system parts.
A mounting stud on the engine will work, but the best place is the bare and exposed terminal on the left front fender well. This is specifically cited in the Owner’s Manual as the place to connect the ground jumper cable clamp. The way to prevent a DTC during a disconnect is to exactly reverse the order followed when making the original connection.
Think of it this way. You want “power” to start the disabled Charger. Start with RED at the Charger, go to the jumping vehicle with the same RED. While you are there, connect BLACK. Finish the job, close the circuit at the vehicle that needs the power, the police Charger. This last connection is the only one that raises a question of where to connect. The other three locations are obvious.
Published in Police Fleet Manager, Sep/Oct 2009
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