In my search for a better alternator i came across a post by ilya5903 on Cumminsforum.com about using a 2001-03 5.9 Durango 160 amp alternator. Today i hit Pull-a-Part and lucked out. They had 2 Durangos and one was a clean 02 5.9 with the factory alternator. $22 + $7 core. Had it tested on the way home and it works. Swapped the pulley and 15 minutes later its on. Definitely puts out more at idle than the stock 136 amp as i can now have all 3 air compressors, a/c, high blower, headlights and stereo on with truck at 800rpm in drive and had 13.9 volts. 14.2 at idle in drive with everything off.

 Factory pn 56029915AA.

https://www.cumminsforum.com/forum/98-5-02-powertrain/2422026-denso-hairpin-160a-alternator-upgrade.html#/topics/2422026?page=1

Good to see that a ford was finally good for something! 

 

Just kidding. I actually don't mind modern Fords. From like 79ish to 2015 ish I'm not a fan. I almost bought a brand new f-150 but I decided on the 2019 GMC 1500 with the 6.2L gas instead. F-ing love that truck.

@kzimmer i can't stand newer fords other than the Vic. I work on them every day. Our fleet is about 90% ford mostly vics, taurus, focus and explorer. Besides the vic complete garbage.

We have some Dodge chargers, challengers, and mini vans. Since I'm the lone Mopar guy i do get every one that comes in. Getting 13 new chargers soon so we'll see how they are. Told they were 5.7 all wheel drive.

7 hours ago, Gregturley said:

Alternator nut thread is m14x1.50. 

There is NOT enough material to cut down the pulley for more thread engagement. The pulley is just under 1/8" (.121") thick in the area that would need cut down. 

My solution is a modified Crown Vic ball joint nut. I cut off the captured washer and the top of the nut that held the nylock insert. I gained 2 complete turns of thread engagement. 

Vic nut on left, factory alternator nut on right

Before and after of Crown Vic nut

That's awesome!  I'll take 2 of those please...while you're at it. 

@Bullet i have 2 more sitting on my box at work. Send me your address.  I'll cut them down and mail them out to you. 

I have an almost endless supply of them on the vics they are a 1 time use because of the nylon insert.

10 minutes ago, Gregturley said:

@Bullet i have 2 more sitting on my box at work. Send me your address.  I'll cut them down and mail them out to you. 

I have an almost endless supply of them on the vics they are a 1 time use because of the nylon insert.

Careful, you might start something.

1 hour ago, Gregturley said:

@Bullet i have 2 more sitting on my box at work. Send me your address.  I'll cut them down and mail them out to you. 

I have an almost endless supply of them on the vics they are a 1 time use because of the nylon insert.

If you find that it works out well for you then I would love to have one of those since I plan to follow your lead...and of course I can PayPal you for your troubles.  I'm waiting to hear your final impressions once you get it all completed and tested like you want it.  

Load tested the alt with stock pulley today. About 110 amps at idle. Didn't get to test at 2000 rpm like i wanted so im waiting to change the pulley until i can. 

 The cut down nut adds right at 2 full threads on the washer side of the nut. It took 3 turns of the stock nut to get the nut flush with the end of a bolt. Vic nut took 5 turns. They are both roughly the same thickness. Definitely has more thread engagement than stock nut and the washer face is just a hair larger diameter.

9 minutes ago, Gregturley said:

Load tested the alt with stock pulley today. About 110 amps at idle. Didn't get to test at 2000 rpm like i wanted so im waiting to change the pulley until i can. 

 The cut down nut adds right at 2 full threads on the washer side of the nut. It took 3 turns of the stock nut to get the nut flush with the end of a bolt. Vic nut took 5 turns. They are both roughly the same thickness. Definitely has more thread engagement than stock nut and the washer face is just a hair larger diameter.

Thanks @Gregturley...can't wait to hear the results of the Ford pulley. 

If memory serves, stock pulley is 60mm and the ford one is 58mm. That's only about a 3.33% decrease. I'd have to see the performance curve of the alternator (rpm vs amps) but if we make up some fuzzy math, you might get as high as 114 amps at idle vs 110 with stock pulley. I never load tested mine so I am very curious. 

It really isnt much difference at all. I don't expect to see much gain but every little bit helps. Plus the Durango pulley was smaller than both of these so i think it might help a little.

I forgot that the 5.9 v8 idles at around 600rpm. Cummins is around 800 so thats a little bump in output assuming the crank pulleys are about the same diameter. Anyone know the diameter of a 2002 Durango 5.9 crank pulley? 01 Cummins crank pulley diameter?

  Crap. More digging to do.

So many different variables involved...I just want to see your final test results.  We should be able to tell a lot from that. 

@kzimmer @Bullet if either of you want one of these nuts (or 2) send me your address. Have 2 ready and will only take a few minutes to do more.

That's really awesome of you to do that, kudos!

With all the stuff going on at work i was never able to load test the alt at 2000 rpm with the stock pulley. Went ahead and swapped ford pulley on today. I don't think i would use the Dodge nut on this even with loctite. Black pulley is Dodge, gold ford. Top alt 136A stock pulley, bottom 160A ford pulley.

 When or if things get better at work I'll load test with the new pulley but it probably won't be anytime soon.

Looks good Greg!  The nut looks like it has decent clearance.  Are you gonna use loctite on the nut too? 

@Bullet used red loctite. I had started getting a small belt chirp over the last few weeks. Its gone with the pulley swap but i know i need a belt. Old one is is oil soaked from all the old oil leaks

What does our 136Amp alternators put out at idle?

Don't know i never tested it. Can tell you it's not enough to charge when the grid heater kicks on and the Durango alt will. It made a huge difference on my truck.

Probably will be a good choice to use a winch with too. Still can't believe Durangos got better alternators than these trucks, stupid Fiat is only getting dumber and cheaper these days, like everything else I suppose, unless it's a Lexus.