I recently upgraded a 2000 civilian crown vic from a 4g civilian alternator to a 6g police unit.

The swap added some additional charging ability (110 amps vs 130 amps). But was mainly done because the voltage regulator in the original 4g unit had failed and was no longer charging the battery. And I had a spare 6g police alternator avaliable, but didn't have any 4g crown vic alternators at the moment.

Since the 6g alternator was factory installed in our cars, all of the necessary brackets and wiring are avaliable from either your local ford dealer or the local salvage yard.

The "new" 6g alternator is on the left, the old broken 4g alternator is on the right

here's a top view of the alternators. notice the different regulator connector and the different orientation of the output stud

here's the regulator wiring pigtail to splice onto the civilian vehicles harness so that a police unit can be installed

here's the factory civilian charging harness. for my purposes, i'll cut off the civvy regulator plug and splice on the police one. the output stud wire has a little different contour to it near the terminal, but can be bent into shape with my bare hands

here's the support brackets for the alternator. the one on the left is the police 6g unit, the one on the right is the civilian 4g

here's the police alternator mounted on the civvy engine block

and here's a picture of the two regulator plugs side by side

and here's a police interceptor with a factory installed 6g alternator for reference

Misc notes:

I should add that the 2000 crown vic lx mentioned in this thread has the digital dash option. So there wasn't a voltage guage inside the car like on the analog cluster. And the regulator inside the alternator also failed in such a way that the charge fault indicator light on the dashboard did NOT illuminate even though battery voltage was so low that the electronic ignition system wasn't functioning properly.


- What is the difference between the civi bracket and the CVPI bracket?

the brackets are a different length between the civi and police cruisers.

when shopping for these brackets, keep in mind that the brackets for crown vics with the aluminum crossover intake manifold are different than the brackets for crown vics with the plastic x-over coolant passage. also keep in mind that the 1996-2000 brackets are different than the 2001+ brackets because these cars use different intake manifolds (NPI vs PI).  a complete list of different alternator brackets is avaliable here.

- Would it be possible to snag a CVPI alty from the bone yard and just grab the wiring harenss & bracket? I'm assuming you had to get a new wire a new alternator plug on to your existing wiring.

Yes, you could grab the alternator, harness plug and bracket from a wrecked police cruiser in a salvage yard. But do keep in mind that the regulator harness plug plastic often gets brittle from the engine heat attacking it over the years. But also keep in mind that the 1U2Z-14S411-TA (WPT-118) harness pigtail pictured above costs close to $30 at your local ford dealer.

- I plan on replacing the serpentine belt soon, with the removal of the alternator, could I get the old belt off and the new belt on without having to loosen the tensioner?

The tensioner in our cars is really easy to loosen tension on. Just stick a 3/8" or 1/2" breaker bar in the hole and twist. And you don't have to completly remove the serpentine belt from the engine to replace the alternator either.

- When I'm sitting at an intersection, obviously foot on brake & turn signal on, my AC fan speeds up & slows down with each blink of the turn signal. Would changing to a higher rated alternator solve this problem?

the civilian engine computers for our cars have a really low commanded idle speed (often 500-600 RPM). you might try boosting idle rpm up to somewhere in the 800 - 1000 rpm to increase charging ability.

also look at what pulley pulley you have on the alternator. a smaller pulley makes the alternator spin faster per given crankshaft rotation. but the smaller pulley will also slip more during big crankshaft rotation speed transistions and also more when driving in wet weather.

- could it be possibkle to add the new 07 200 amp alternators on my 03 cvpi? wihtout to much modifacation ?

the alternators in the 2002 & earlier crown vics use a conventional i-line voltage sense regulator to control alternator charging. the rest of your crown vic's powertrain management system effectively does not know which alternator model you have installed in your car.

the alternators in 2003 & later crown vics are pcm controlled. the pcm communicates with the alternator regulator via a databus. and your pcm calibration must be compatible with your particular alternator model.

I downgraded the Alternator to a Civy on a 1994 P71, same idea but even easier as no support bracket to worry about.

the alternator support bracket on the 1998 & later crown vics appears to be a factory installed crash bracket to improve the integrity of the passenger compartment during a frontal collision.

starting in 1998, a crash bracket of similar thickness was also installed on the rear of the engine to help prevent the fuel rail from banging against the firewall and wiper cowl during a frontal collision.

on the 1997 & earlier crownvics, the bracket near the alternator supports the spark plug wires. but 1998+ crown vics, use a coil on plug ignition system and don't have any high voltage spark plug wires to support. so the bracket has been redesigned to help prevent passenger injury during a high energy frontal collision.

Do I need the alternator top support bracket?

Yes. Without it, your alternator will rock forwards/backwards as your engine runs and eventually break the lower mounting bolts. Click here to watch a video of a crownvic alternator with the top bracket removed leaning forwards/backwards as the a/c compressor engages/releases. Another video from a different angle is avaliable by clicking here. And discussion thread about this topic is avaliable by clicking here.

Do note that you need MPEG4 support to view these videos. Microsoft windows 7 has this builtin. But with microsoft windows xp, you will need to install apple's quicktime software from here.

Can I modify the "wrong" alternator top support bracket to fit in my particular application?

Some alternator support brackets can have a couple extra holes drilled in them to accomodate different alternator & intake manfold models. Click here and here to view a couple pictures of such a modification.
But for long term durability and ease of installation, it's recommended to use the "proper" support bracket in the first place.
-Ok, i just did this upgrade on my car today. I needed to do it cause of my stereo system. I did notice one thing though. The factory harness on my car(2000 crown vic lx) only has 2 wires and the aftermarket pigtail comes with 3 wires. Do we use all 3 wires or just two? I only used the two outter wires. any pics of which wire goes connected where?

yes, you only need to connect the outer two wires on the wiring pigtail.

one of the wires will remain unused. on a factory police interceptor this cavity in the connector would not even have a wire in it.

there are some pictures of the connectors located here.

Is a 6G alternator better than a 3G or 4G alternator?

The 6G alternators have better cooling than the 3G and 4G alternators. The sixth generation (6G) alternators also have more durable bearings too.

In light civilian use, a 3G or 4G alternator will probably do you fine. But, if you have added high draw accessories like a powerful aftermarket stereo system or lots of police radios/lighting equipment, then a 6G alternator would be a better choice for your car. A loaded alternator generates lots of heat, and overheated electrical components will usually have a rather short lifespan. Note the large amount of open airflow cooling space on the front of a 6G alternator compared to the 3G and 4G alternators.

-How does the pcm control the alternator on model year 2003 and later crown victorias?

click here

What happens if I install an alternator intended for a 1998-2002 crownvic into my 2003+ crownvic?

Sometimes, you'll get lucky and the alternator will charge. But even in the best case scenario, you'll have a P0622 (Generator Field "F" Control Circuit Malfunction) error code present and the charge light illuminated. The alternator may charge because:
-both the pcm controlled regulator & the non-pcm controlled regulator use the same electrical connector
-battery voltage is present on pin 3
-pin 1 is pulled logic high by the pcm alternator field detection circuitry like it would be by the alternator charge bulb. do note that this is a low current feed which may not be sufficent to excite the rotor field coil on certain alternator models.

How do I get a 2003+ crownvic PCM controlled alternator to charge in a pre-2003 car?

You are opening up a whole can of worms here. It would be much easier to acquire the proper pre-2003 alternator for your pre-2003 crownvic. If you are adventurous and want more information about this retrofit, click here.

Pin 2 of the 6G alternator regulator connector in my 1998 crownvic is empty. How do I insert an extra pin into my exisiting alternator connector so that i can send gencom data to a 2003+ alternator?

You don't. The regulator connector shell plastic in the 1998-2002 cars isn't designed to accomodate an extra pin. You will need to purchase a new regulator connector pigtail with 3 pins already in it like ford part # 1U2Z-14S411-TA (WPT-118).

What alternator models are compatible with the PCM in my 1992-2002 crownvic?

The powertrain control modules in the 1992-2002 cars actually have no idea about which alternator model is installed. You could remove the alternator all together, and install a big external a/c charger and the car wouldn't know any different. And you wouldn't get any powertrain error codes either.

Courtesy of dRock96Marquis:

(note: must be a registered user on crownvic.net in order to view this particular thread. registration for this website is free, but registrations are manually approved. so there may be a several hour delay between when you register, and when your registration is approved)

4g to 6g Panther alternator upgrade - by 2vmodular

The following article applies to 1992+ Crown Victoria, Grand Marquis and Lincoln Town Car.
1998+ CVPI models have a 6g alternator and boast a higher charging output than their retail model counterparts with the 4g alternator. If you have a -1997 Panther you will actually be converting from a 3g rather than the '98- (non-CVPI) 4g outlined below, but the retrofit is the same. Note -'97 models have spark plug wires and a 6g alternator was never offered, so there is no direct-fit alternator bracket available for this combination (The spark plugs clip onto the bracket on '96/'97 models). Likewise there was no 6g alternator for '92-'95s which have the all-aluminum intake manifold, so something will have to be fabricated.

If you have a 2003+ the procedure is essentially the same but you MUST use a 2003 or newer alternator (PCM controlled voltage regulator) and may require a PCM calibration reflash. Note 2004+ CVPI have a high-output 200amp alternator with one-way clutch with eliminates belt chirp and prolongs belt life.

Also note the brackets are different between the composite and aluminum front coolant crossover '96+ manifolds.