Ok so my alternator went out today on my 03' Cobra. I wanted to share some interesting info besides the fact that it is an absolute pain in the arse to remove and replace.
A mechanic told me that if you suspect your Mustang alternator is dead you can do this quck check. Turn your key all the way to the point before the car kicks over. If the the dashboard battery light DOESN'T turn on when you turn your key then the alternator could still be good. Apparently when that light bulb/fuse (not sure which) goes dead the computer will turn off the alternator. Therefore, if the battery light doesn't show then all you need to do is replace that bulb or fuse. BUT, if the light does turn on when you turn the key then you more than likely have a dead alternator.
I very well may have misunderstood the mechanic but I believe I got it down right. If anyone has anything to add please do so. Just trying to help people out in the future!
Also, does anyone know if it is worth going after an aftermarket alternator or just better to go with an OEM?
No, I'm not running anymore boost. Everything is stock except for my exhaust and K&N air filter. There was an 01 GT owner in there with me getting his replaced and the mechanic mentioned how he didn't understand how they go out so quick on mustangs. Mine only has 39k miles, kind of early don't you think?
you hook a volt meter to your battery to see what it was getting? like 14 volts or so? i got a 6lb lower pulley i had to change my alt pulley to a 3.20 size one. yes it hard to get to i must say. but if its got to be done you must do it. or does it read battery voltage when cars running?
< Message edited by freewilly -- 9/27/2006 9:48:24 AM >
Yeah we checked to make sure it was the alternator. I then had two mechanics confirm. I'm not sure I understand all of your message freewilly - "or does it read battery voltage when car running".
In any case, some other interesting info on the alternator...I'm having FORD put it in for me and I had one dealership quote me 3hrs MINIMUM of work @ $100/hr. Now if it was just a regular GT it would have been considerably cheaper. In any case I told them they were crazy and luckily found another Ford dealership quote me for 1hr labor @ $75. 1hr vs 3hrs and $75 vs. $300 is a HUGE difference. No worries, I checked with the tech specialist and sales manager to confirm that $75 price was for an 03 supercharged cobra. I just think its funny how some places (even ford) will try to jerk you around just because you have a limited production car, ie. Cobra.
Next purchase - Car Cover. Gotta keep it lookin mean AND clean!
Funny you should say that. Mine is going out too,and the new one is on order but, It will take 3 weeks to come in. . and I only have 11,000 miles on my 04 cobra. The battery light goes on when my RPM's are low. I have already changed the battery. Another test you can do if you have a stickis. while you are driving, turn the engine off and hold down the rtrip button by the stearing wheel and turn the car back on and if you will press the button you will go through a list of about 30 things; one of them will be the battery. It shows you the volts at any given moment. It's a secret test system ford put in. Well I'm not sure if you understand that but, I'm female and I don't always know the correct words to use. I just know How to do it. Anyways, I am having a shop install the new one. The cost is over $450.00, but, worth it.
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2004 Mystichrome Cobra Chic Owned!!! Pro 5.0 Shifter QMP Exhaust 2.76 upper pulley JLT High Boost Ram Air 315/35/17 Nitto 555r DR on 9" wheels Gords Heat Exchange (next)
When you find a place to purchase a really good car cover, Please post it. I need one too. I have the Mystichrome and every bird seems to like it....... A lot.
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2004 Mystichrome Cobra Chic Owned!!! Pro 5.0 Shifter QMP Exhaust 2.76 upper pulley JLT High Boost Ram Air 315/35/17 Nitto 555r DR on 9" wheels Gords Heat Exchange (next)
People, alternators are meant to be rebuilt. You probably replaced yours with a rebuilt one anyways. Just find a shop to do it, and tell them to beef up the rotors and stators for more amperage. They put a weak ass alternator in our cars. I have had my car pullied for the last 45,000 miles with no issues with my alternator, absolutely none. But when and if I do, I will have it rebuilt for less than a 100 with more amps. Of course, I'm running a BAP and a 6lb, so more stress is on it right now and I expect it to not last in stock form for much longer, but who knows. I did change the alt. pulley though to get that ratio close to stock.
< Message edited by AllVenom -- 10/11/2006 3:20:09 PM >
You can definitely save money having it rebuilt, although sometimes folks want a high-performance replacement or don't want to wait for the rebuild. You know, I've been seeing more and more 2003/2004 alternators going bad. Very unusual and I hope it isn't a warning sign that the stock alternator has longevity issues. I can understand one going bad due to the lack of a larger alternator pulley when a larger crank pulley is used, or if the car sees a lot of track racing, but many of these failures are on cars that are near stock and rarely raced. Not good.
I don't believe alternators were MEANT to be rebuilt but either way I did put in a brand new Ford built unit (not rebuilt). I saved considerable money on the part thanks to the company I work for. So for the cost savings and reassurance of replacing it with an OEM part, it was a no brainer for me. I do understand how typically its cheaper to go rebuilt but some people just want the peace of mind and warranty provided by having the same part put in that came w/ the vehicle off the assembly line.
I do hope that CobraBob isn't correct in his diagnoses of all the 03/04 alternators having longevity issues or else I may have made a slight mistake in my replacement part. Hopefully this is figured out before too many others lose their alternators.
Yea the problem must be in the 03/04's only... mine has never had that prob. Anyone have this issue on a 99/01?
You won't find this issue in the 99/01 because there's no power adder overspinning the alternator.
Cobrabob, are you sure these failures are 03/04s in stock form? Most of the failures I have read about on svtperf were from pullied cars.
Both. I can tell you that for a fact. I would think, though, that the greater majority are from Terminators in the following two groups. 1. Those that see a lot of high RPM spinning of the motor (track, street racing, etc.). I know of one stock (or near stock, I forget) Terminator with only 15K miles on it and the alternator went. 2. Those that have 4 lb. or 6 lb. lower crank pullies with the stock alternator pulley. A 3.2" should be used with the 4 lb. and the 3.4" should be used with the 6 lb. Otherwise you are spinning the heck out of the alternator, thus shortening its lifespan.
Yea the problem must be in the 03/04's only... mine has never had that prob. Anyone have this issue on a 99/01?
You won't find this issue in the 99/01 because there's no power adder overspinning the alternator.
Cobrabob, are you sure these failures are 03/04s in stock form? Most of the failures I have read about on svtperf were from pullied cars.
Both. I can tell you that for a fact. I would think, though, that the greater majority are from Terminators in the following two groups. 1. Those that see a lot of high RPM spinning of the motor (track, street racing, etc.). I know of one stock (or near stock, I forget) Terminator with only 15K miles on it and the alternator went. 2. Those that have 4 lb. or 6 lb. lower crank pullies with the stock alternator pulley. A 3.2" should be used with the 4 lb. and the 3.4" should be used with the 6 lb. Otherwise you are spinning the heck out of the alternator, thus shortening its lifespan.
Agreed. I changed to the 3.5 when I put the 6lb on mine. I did not change the alt. pulley when using the 4lb though for about 10 months. But I also didn't have a BAP putting strain on it in that form either (not that it is much of a strain, but nevertheless an addition). I guess I have been lucky up to this point with the alternator.
I really dont frequent these boards alot but I can tell you I will be on 4th alt now. I have an upper pullley and stock lower with a larger alt pulley to slow it down and they have all went out. An upper pulley doesnt affect the speed the alt is going, its just the crank pulley. I have never in the the life of the car taken it to the track or race it anywhere. I have gone through the ford oem, pa alt. and now the autozone one.
I think the alternator on my bone stock 03 Cobra died today, with only 38K miles on it. The car wouldn't run after being push started, with lots of strange lights on the dash, most notably, ABS and airbag. If there is a battery or alternator light,I didn't notice it, would it have killed Ford to include an ammeter gauge? I don't know if it took the battery with it, I'm hoping not, but if so, I'll be replacing it with a Optima yellow top.
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Alternator Info - Cobra - 
