Alternator Issues

[mgauger]

Bought a new Tuff Stuff alternator, this is the 175 amp, not the 250. When I installed it and started the jeep, which is a 2013 with the 3.6, the volts jumped straight up to 18+, all lights on the dash came on and fan started blowing on high, even though it wasn't on. Shut her down, installed the stock alternator, and everything is fine.
Called Tuff Stuff, they told me it needed to be grounded?? So, to appease them, ran a ground from one of the bolts to the neg battery terminal,,,,,same this, volts went to between 18 and 19 and every light come on the dash.
So,,,,I hear about people running high output alternators with no issues but I got to think it has to do with it being a higher output then stock. Any ideas on what is going on here? I sent the alternator back to them and there telling me it checks out just fine. So I assume it's the internal regulator that isn't liking the higher output, even though it's only what 15 more volts then stock.
Any input would be greatly appreciated.

Thanks

 

[BLACKJKU]

Is this alternator sold specifically for the JK? Does the alternator have a internal regulator? The JK's ECM controls the voltage for the alternator.

 

[mgauger]

Hi, yes, sorry, should have mentioned that,,,,it is a direct bolt in for 2012 - 2018 jeep wranglers.

Thanks

 

[BLACKJKU]

The stock charging on my JK is 14.7 so 18 to 19 is way to many volts. Do you still have the alternator if so take it to a Auto Parts store that tests alternators and see what it does on there machine.

 

[mgauger]

Exactly,,,,I mailed it back to Tuff Stuff and they told me it tested just fine. They said they would send me out a new one but if that didn't work they said it would have to be a issue with my ECM, but it works fine with the stock alternator. The stock unit started making a chirping noise when warmed up,,,,,still charges fine but the chirping drives me crazy when I'm out crawling so decided to get a new one and keep the stock for a backup if needed.
I guess my question is, could it be a issue with my ECM?? Do they need to be programmed in anyway, if you are installing a higher output alternator? Thanks again for the help!!

 

[BLACKJKU]

If it was a problem with your ECM the stock one would be causing a problem also. There has never been any programming that needs to be done on a alternator that I've even known about. A high out put alternator is just the amps not the volts.

I bought a slightly higher amp one wire alternator for one of my old Dodges and it charged slightly over 15 but settled down to 14.6 after a few miles. But 18 to 19 will cause all kinds of electrical problems along with blowing up a battery. I've even heard of 16 volts blowing up a battery.

 

[mgauger]

Appreciate the help,,,,guess I'll wait and see if the new one they send does the same thing.

Thanks again

 

[BLACKJKU]

Let us know I notice while Googling there are other companies that sell alternators and the only thing I saw they say is just a bigger battery wire to put the extra amps out to the battery.

 

[jeeperscreapers]

Exactly,,,,I mailed it back to Tuff Stuff and they told me it tested just fine. They said they would send me out a new one but if that didn't work they said it would have to be a issue with my ECM, but it works fine with the stock alternator. The stock unit started making a chirping noise when warmed up,,,,,still charges fine but the chirping drives me crazy when I'm out crawling so decided to get a new one and keep the stock for a backup if needed.
I guess my question is, could it be a issue with my ECM?? Do they need to be programmed in anyway, if you are installing a higher output alternator? Thanks again for the help!!

i am looking at the same one for my 2010, did you ever get an answer...?? ty

 

[Vman]

Let us know I notice while Googling there are other companies that sell alternators and the only thing I saw they say is just a bigger battery wire to put the extra amps out to the battery.

Theres your problem.

The stock cables need to be upgraded to a larger gauge.

 

[Vman]

i am looking at the same one for my 2010, did you ever get an answer...?? ty

Didn't notice this was from a while ago.

A higher output on the alternator requires you to install better battery/ground wiring.

High-Output Alternators Save the Day

It doesn’t matter whether it’s in the deep chill of winter or the heat of summer, on a work truck, emergency vehicle, or personal rig—the last thing a driver wa

www.motortrend.com

 

[jeeperscreapers]

Theres your problem.

The stock cables need to be upgraded to a larger gauge.

so that tuffstuff alternator should work fine as long as i upgrade the wiring....

Tuff Mudder 7513G 175 Amp Alternator from Tuff Stuff fits 2007-2011 JK Jeep Wranglers

7513G High Amp Alternator from Tuff Stuff fits 2007-2011 JK Jeep Wranglers and provides nearly double the factory output to power high amp accessories

www.tuffstuffperformance.com

 

[Vman]

so that tuffstuff alternator should work fine as long as i upgrade the wiring....

Tuff Mudder 7513G 175 Amp Alternator from Tuff Stuff fits 2007-2011 JK Jeep Wranglers

7513G High Amp Alternator from Tuff Stuff fits 2007-2011 JK Jeep Wranglers and provides nearly double the factory output to power high amp accessories

www.tuffstuffperformance.com

Yeah I would think so. Just checked and they do market directly for our JKs.

There are at least two companies that sell complete wiring upgrade kits that are ready to stick in for the JK and other Jeeps.

Only other thing you might want to do is check your mesh style grounding straps from hood to frame/frame to block.

IMHO the electrical system is probably the most important, and most overlooked, system in the vehicle.