So I searched on here and came to the conclusion that are alternators are 130amp. But while searching online for ford oem parts the biggest I could find was 120. I know about the 200 and other options there are but I'm trying to just replace it with what exactly is on there.

This is all I could find for motorcraft (120amp),
2000: 8Cyl 5.4L Supercharged, Gas, Fuel Injected, VIN "3" LIGHTNING

Anybody have the stock alternator #?

 

I don't know the part number, but be very careful, our stock alternator pulley is NOT the part number listed everywhere.

If you change your alternator, make sure you use your original pulley. As far as I can tell it's impossible to find our stock pulley.

 

Great tip, but out of curiousity, what's the difference between the two?

 

Thanks, I saw that while i was searching. I guess it eats up belts if you don't use the stock pulley. I was planning on just bringing the old one with me when I pick up the new one and have them put the stock one on the new one. The ford dealers I called said it was 120amp and part stores i called said all they had for it was a 130amp.

 

I got the correct alternator from NAPA, it already had the proper 8 rib pulley on it.

 

Tim,

The 'standard' F-150 pulleys are 8-rib too but they are offset (I can't remember exactly if it's inward or outward) by about 1/4". The Mr. Alternator high-output I got came with the F-150 pulley even though it was listed as a Lightning-specific alternator and you could visually see the difference in the pulley offset.

 

I also replaced my alternator, got it from NAPA, and they deliver it right to my door!

When I first looked at the old alternator and seen the ribbed pulley, I said dam, how am I going to pull this off, and install it back, but just as I was removing the old one!

The driver pulls up and shows me the box, and as soon as I seen it, it all ready had the ribbed pulley on it, re-installed it, and it has been running great, pushing up to 14.0 volts sometimes… The L is up to (96 K) barely breaking her in, and she is behaving just fine…….

 

As other people have mentioned, the pulley is basically one rib to far out from the alternator.

 

Ditto. I had the same problem with a Mr. Alternator pulley. It was making the belt ride one groove off the next pulley. I switched to the one off my original alternator and problem solved. Now I need just a pulley for my Expedition conversion alternator and Ford can't seem to find the correct one?

 

ASP Racing 1 877 928 8678 they can make you a pulley (did for me) was really pretty cheap...