Pretty sure mine is factory. I have 63k miles on it? It does seem to be getting a little weak though so I've been thinking about replacing it.. Power windows are rediculously slow if anything else like headlights are on and also vice versa, headlights dim bad if they're on and I go to put a window up or down.
Haven't checked the alternator to see what kind of voltage its putting out yet, but Im pretty sure its the battery.
That is usually the alternator. When they are about to go bad that its. When your car is on the alternator does almost all the work for the windows, lights, wipers, etc... Looks like your going to be in the market for a new one.
Mine was fine until I installed an aftermarket stereo. I run a total of about 1000 watts rms to my entire system with a 1 farad cap. With the pullies, I try to turn the music down when the car is idling, but sometimes I can't help myself. Music was meant to be loud! Anyway, I think I abused it too much. It has gone dead on me like twice this month. Time for an Optima and to relocate it to the trunk.
The Motorcraft batteries seem to be good ones. My Stang is still going strong after 2 years. The one in my 91 F-150 lasted over 8 years in the high hummidity summers and cold winters here in Maryland!
My dash lights dim when I roll both windows up or down. It's done it ever since I got the car about 2 years ago. Saw a dummy light a couple times about a year ago, fine ever since When I bought the car it had a receipt for a bunch of stereo equipment (not in the car anymore), so maybe that stereo abuse some how messed up the alternator...
I had in both my SVO and Cobra the original Motorcraft batteries and they lasted about four years. If your having problems now, replace it. The cold winters are hardest on our batteries. I forgot to replace mine in the Cobra a few years ago around this time. Got stuck in the middle of the night and had to call a friend to pick me up and then we had to look for a battery at the parts store. The only good quality battery available was a Delco so I put that in . Hey, you couldn't tell anyways if I have a GM battery, the cover masks it.
do all of you check the water level in your batteries every 3-4 months? i have noticed that i have to add water every 6 months or so. if you don't, you can ruin a perfectly good battery. mine is 3 years old with 33k miles and the green dot is bright when the car is running and after i turn it off.