I have a 2003 F350 5.4. I bought it used and had a Blizzard 810 plow installed. I got the build sheet that got from the parts department and it listed the truck as having a HD alternator. Does anybody know how many amps this alternator is? I really need at least 130 amps. The lights dim when the plow is working. I know that the truck will die in the middle of a storm if I start running the lights, defrost, and all the other with the plow. I don't want to wait untill it starts snowing. Where is there a good source to buy a 130-140amp alternator that is a straight swap? Should I just go to Auto-Zone or Pep Boys? There must be a better source. Ebay has plenty but I don't know which one to get. Thanks in adavance.

 

The SuperDuty alternator puts out 90-100 DEPENDABLE amps. They are rated higher, but that's cold. When they warm up the output goes down.

As far as a higher output unit, around here we have them custom wound at a local rebuild shop that rebuilds for all the chains for not much more than a rebuilt unit from the parts store ($175). Of course we've cut the parts store out of the equation so that helps 160-180 amps is what most plow/winch guys go for.

 

According to the 2003 sales brochure, the standard alternator on all engines was 130 amps. On the diesels, you were able to get dual alternators for a total capacity of 260 amps. There were no optional HD alternators available. I have a Fisher plow on my 03 F-250 5.4L, and I have had no problems. It is normal for the lights to dim when you are lifting or angling the plow, but they should brighten up as soon as you release the lever. Have your battery tested--it's 3 years old already--it was probably manufactured back in 2002. If it's starting to go bad, the voltage will fall more than usual when you are drawing heavy amounts of current from it. I own an auto repair shop, and I usually recommend an Interstate MTP-65 battery for any Ford with a plow on it. If you can find a local starter/alternator rebuilder in your area, they can probably rebuild it using a higher capacity rotor & stator and possibly get 20-40 % more current capacity out of it.

RON

 

Whens the last time the plow motor was serviced ?
I run a fisher plow on my truck since 02 same alt/same batt no problems but I chnge my Hydraluc fluid every year and keep all my pivot pins greased.plus I clean all electrical connections every yr.
Have your alt/batt chkd, but also do mait.on your plow system

Rich

 

I've only seen or read about "130" amp alternators in the '01 and up SD's (the 130 is in quotes because it can't really put out 130 amps at the normal under-hood temps).

There is a bigger rotor/stator, rectifier and regulator available for the "3G" series of Ford alternators that put out up to "200" amps - again, that's most likely cold output.

There is also an upgraded rectifier available for the "130" amp alt that will make it at least dependable at that 90-100 range. At idle, it's a different story, you'll only get about 60 amps from the 130, and 100 amps from the 200.

I see lots of 200 amp alternators on Ebay all the time. Even though they say "new" they are standard 130 amp cases with the 200amp parts thrown in, so that's not necessarily "new" but "rebuilt with higher output parts"

Or, you could go to a local alt rebuilder and see what they can do for you - there's two ways to go:

1) Use your standard 130 amp 3G alternator, but replace the rectifier with the upgraded part - this will give you the same output, but it will resist overheating and frying itself.

2) Replace the stator, regulator and rectifier with 200amp parts.

I plan on doing #2 myself one of these days when I get a spare alt to use as a core.

Also, you have an 8-groove pulley. If you plan on buying another alt, make sure it has the 8-groove pulley.

art k.

 

I have a lot of experience with the ford 3g (130A) alternator you are talking about, it is one of the very best ford has ever built, it is super reliable and the output is decent. Plows require tremendous amounts of power for very short periods of time which is why you see the lights dim, an alternator cannot compensate for this. I own an 04 5.4l with a Western 8.5 blade, I installed dual battery's just for this reason and am very pleased with the results. I think you will be fine with your alternator and I recommend that you beware of these high output mods as they are mostly made with inferior quality parts and rarely put out what they claim. If you are still worried you might want to think about the dual battery idea, out of all the guys I have plowed with none have problems with dual battery's and some without do.

 

The 3G's rectifier is a known "weak link" in this particular alternator.

Transpo makes a HD replacement, and also makes the other 200 amp upgrade parts I was talking about.

But back to the original intent, sounds like you should be fine, but have your existing battery checked. If it's not up-to-snuff, get the highest CCA battery that will fit.

 

Thank you for all the replies. I just bought the truck and its a 2003. I will get the battery checked and see how the alternator is also. I had my 2000 F350 6.8 die while I was using it last year, it was out for three days straight in a blizzard with 36" though. The battery was 5 years old and was replaced along with the alternator. The lights didn't dim as much after but always dimmed a little. Didn't have any problems after that. I just don't want to get stuck once it starts snowing. The plows have all been serviced and checked out. The Blizzard 810 is not like a Fisher plow and has a lot more moving parts and will draw more. It more than makes up for this with speed of snow removal once you start using the wings and the 10' feature. Does anybody use the Optima battery? would this be a close alternative to two batteries or is that the best way to go? Thanks again and great forum.

 

my dad has a 2001 f150 5.4 crew cab what alternator does he have? the 90 amp one or the 130? i need to know because they are asking him which one it is at the parts store due to larger external dimensions. by the way its a nice forum glad to have found it seems like it will be alot of help here.

 

Eduardo Welcome to the site.!!

I agree with Krewat he seems to have done his homework on the 3G. I rebuilt mine to the 200 amp spec including the high output regulator 14.7 volts..You also have to run a 4 ga wire from the alt to the batt and a monster fuse, I always use a 1000 cca battery. I can have lotsa lights on and plow and never worry. The regulator helps with idle amps and light brightness but you have to use the 4ga wire like I said if you want top performance.

The 130 amp alt while looking at the front has rect box with two holes in them the 90 amp has square box with 4 holes in them.

Dick