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Alternator Amps


jggtjr

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I am trying to figure out how many amps my stock 4.0L Ranger alternator produces and draws regularly. I want to know if it has enough amperage to run 4 9" roof rack lights that each draw 6 amps. Any help is appreciated. Thanks.
 


AgPete139

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Run it and tell us how it goes. If your lights dim, upgrade then. And for the record, amperage has been discussed. Did you try the search?

Pete
 

jggtjr

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No, but I will do that right now. And I'm also thinking trial and error is the best way to find out haha...
 

PlumCrazy

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Your truck most likely has a 95 amp alt, which should hold up just fine to the roof lights. How many watts are they? I am pretty sure it only takes around 40-50 amps for the truck to run, the remanding 50-30 amps is for things like headlights, power windows, 4x4 shift motor, wiper motor etc. So as long as you dont turn the lights on, run both power windows up and down, put the wipers on high, and put it into 4x4 over an over, you wont notice the extra amp draw.

My 130 amp alt holds up fine to 6 130w KC's, and 4 50w headlight/fogs, and 4 50w back up/puddle lights. When they are all on they draw about 70 amps @ 13 volts

My 1000w rms amp is enough to dim the lights and drop the system down to about 8 volts. When my subs hit peak power they draw around 75 amps.lol If I turned all the lights on and cranked up the stereo, I am sure I could fry my alt, but I have no reason to turn everything on at the same time. Now that doesnt mean I am not looking for a cheap 200 amp alt though.


Watts/Volts=Amps

-plumcrazy
 
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jggtjr

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Thanks for the information. I think I should be just fine. I'll give it a shot and see how it goes.
 

AllanD

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I am trying to figure out how many amps my stock 4.0L Ranger alternator produces and draws regularly. I want to know if it has enough amperage to run 4 9" roof rack lights that each draw 6 amps. Any help is appreciated. Thanks.
The Stock alternator is either a 95Amp, a 130Amp or a 160amp

In any case there is enough alternator to run 24amps worth
of aux lighting.

When I swapped a 1993 4.0 into my 1987 Supercab I also upgraded
the power distribution and installed a 130amp alternator, mostly
because it amused me to be installing an alternator with THREE TIMES
the capacity of the alternator the factory installed on the truck.

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