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Dual Alternator install

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Michael, I am planning on upgrading the oem 136 amp Bosch alternator on my 2005 with either the 160 amp Denso or perhaps the single 220 amp Denso alternator. I have a couple questions for you regarding the 220 alt--

1) Do you know if the single 220 amp Denso be plug n play on a 3rd gen 5.9 CTD (other then upgrading the wires) ??

2) Do you have a part # for the 220 amp alternator ??

3) Do you know how to avoid the 220 amp alternators that were recalled due to diode failures and fire hazard?

TIA!!!
 
Michael, I am planning on upgrading the oem 136 amp Bosch alternator on my 2005 with either the 160 amp Denso or perhaps the single 220 amp Denso alternator. I have a couple questions for you regarding the 220 alt--

1) Do you know if the single 220 amp Denso be plug n play on a 3rd gen 5.9 CTD (other then upgrading the wires) ??

2) Do you have a part # for the 220 amp alternator ??

3) Do you know how to avoid the 220 amp alternators that were recalled due to diode failures and fire hazard?

TIA!!!
Try RockAuto for the alternator, post 2008 there was some changes on the alternators from what I have found so far. Mine is a 2009, the connector changed, if you can take a picture of your connector on your existing, I could lock it down for you. Also check out the Remy technical bulletin I linked earlier, it shows the styles of connectors.
As far as the recall units go, from reading up on the recall, and the mode of failure, it was an issue with a short circuit in the diode assembly, any remanufactured unit should have, and I say SHOULD.. have new diodes. Not all 220A units were affected, there were specific one's.. somewhere I found the actual recall instructions for that 220A issue, it refers to a specific Denso part number, which is not available anywhere.. so hopefully that means it's not an issue. The second Remy remanufactured unit appears to be performing well, I used to work in auto parts, thus hesitant to go reman.. but when it's less than half the cost, it's pretty hard to resist, and fortunately it's not too difficult to swap out on these trucks.

 
Status of wiring investigation.. I had a very experienced expert on the subject review my ideas and he suggested a different path. I have a $4.37 part on order the that essentially would duplicate the ECM power signal to the second unit. The problem with series connection is Ohm's Law. The double field resistance would half the current for the same field voltage, it would half the max output of each alternator, while that would serve for redundancy, and clearly would make each work under less steess, it prevents the ability to use additional power, which would be useful. I still plan to incorporate a switch network to allow single unit operation, on either unit.. which could come in handy for redundancy. More to follow.
 
Very interesting following along with you on this...keep up the updates!



I hate to get you sidetracked at this point, but have you looked at Mechman's alternators they offer? I picked one up about a year ago, and it's been flawless.

They offer 140 amps charging at IDLE...and 320 amp full boar. Not bad for a drop-in replacement. http://www.mechman.com/alternators/...20-amp-alternator-for-06-09-5-9l-cummins-ram/

--Eric
Eric,. Yes I looked at those and Mean Green. They are North of $400, granted I'm looking at something close to that at this point, but the advantage of Dual is built in redundancy and back up. Also heat is generally what kills alternators, having twice the surface area and twice the fans, etc. Plus when OEM is doing it on new trucks, not one extra large.. and they cover it under warranty.. good chance it will hold up well. More to come when I get back from a trip..
 
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Micheal,

I am trying to confirm if there is an OEM 220amp alternator that might be plugn'play for my 2005 5.9CTD with the OEM Bosch 136amp unit (pictured below)

I do NOT mind changing brackets or belts and alt wire will also be upgraded.

Bosch136a_ALT.2.jpg
 
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Micheal,

I am trying to confirm if there is an OEM 220amp alternator that might be plugn'play for my 2005 5.9CTD with the OEM Bosch 136amp unit (pictured below)

I do NOT mind changing brackets or belts and alt wire will also be upgraded.
Ok, best I can tell is the 220A uses the single field wire, internal grounded field regulation, which began in 2008. From the Remy technical bulletin I posted earlier, you'll have a system that uses 2 wire field regulation. The 220A would otherwise work bolt-in, no apparent changes in mounting brackets. So, if you want to do this, you would have to MODIFY the unit such that the field has both sides connected to your truck via the 2 wire connector. See the pictures of the Denso unit I posted earlier. The brush holder has 2 screws that hold it in, and connect the field windings. One goes to the connector, the other to ground.. you'll have to break the connection to ground ( insulate with plastic, etc. Then run a wire out to make that second connection. That I think would work.

 
Ok, best I can tell is the 220A uses the single field wire, internal grounded field regulation, which began in 2008. From the Remy technical bulletin I posted earlier, you'll have a system that uses 2 wire field regulation. The 220A would otherwise work bolt-in, no apparent changes in mounting brackets. So, if you want to do this, you would have to MODIFY the unit such that the field has both sides connected to your truck via the 2 wire connector. See the pictures of the Denso unit I posted earlier. The brush holder has 2 screws that hold it in, and connect the field windings. One goes to the connector, the other to ground.. you'll have to break the connection to ground ( insulate with plastic, etc. Then run a wire out to make that second connection. That I think would work.



Thanks for that info! That being said, I do NOT want to blow up a $400 alternator... Are you SURE it's that easy ??
 
Thanks for that info! That being said, I do NOT want to blow up a $400 alternator... Are you SURE it's that easy ??
You should be able to get a 220A from RockAuto for less than $200, granted a reman, but that much less it's worth it to try, if you don't like the quality it's returnable.. I returned the first one due to voltage fluctuating, no issues. Take a look at the REMY technical bulletin, it shows the different regulator set up for Chrysler. As long as you ensure neither side of the field windings ( each of 2 brushes ) is NOT grounded, and you have each side connected to your original wiring harness.. it should work.. nothing will fry. Also, it doesn't matter which direction current flows in the field, either way produces same output, since it's AC rectified to DC via diodes.

 
You should be able to get a 220A from RockAuto for less than $200, granted a reman, but that much less it's worth it to try, if you don't like the quality it's returnable.. I returned the first one due to voltage fluctuating, no issues. Take a look at the REMY technical bulletin, it shows the different regulator set up for Chrysler. As long as you ensure neither side of the field windings ( each of 2 brushes ) is NOT grounded, and you have each side connected to your original wiring harness.. it should work.. nothing will fry. Also, it doesn't matter which direction current flows in the field, either way produces same output, since it's AC rectified to DC via diodes.



Alright, that is more reassuring and I could probably do that, though still might goiw with new as opposed to reman in China.

Thanks again!!!
 
Alright, that is more reassuring and I could probably do that, though still might goiw with new as opposed to reman in China.

Thanks again!!!
Totally understand hesitation on a reman.. however I was surprised it was the USA Reman I got that was of questionable quality, while the second unit was a China reman an looked perfect.. sad when that is the case, I know.. but the China stuff has been improving over the years.. it's no longer a sure sign of poor quality that it once was, and sadly USA made is no longer a sure sign of quality.. I had less than one year old USA made Dexstar trailer steel rims, one of which developed a crack, and not at a weld.. that surprised me.. meanwhile the OEM crap China wheels I had replaced never had any problems, I replaced them only to get a larger diameter for better tires.

 
Totally understand hesitation on a reman.. however I was surprised it was the USA Reman I got that was of questionable quality, while the second unit was a China reman an looked perfect.. sad when that is the case, I know.. but the China stuff has been improving over the years.. it's no longer a sure sign of poor quality that it once was, and sadly USA made is no longer a sure sign of quality.. I had less than one year old USA made Dexstar trailer steel rims, one of which developed a crack, and not at a weld.. that surprised me.. meanwhile the OEM crap China wheels I had replaced never had any problems, I replaced them only to get a larger diameter for better tires.

Score 2 for the China Reman.. sad days. The China REMY Reman is working well, and just did over 5500 miles of towing to verify.. in the meantime ordered the second, and opened it yesterday.. a USA Reman from Remy.. the 2 pin connector plug is not new, with bent pins and damage to the connector housing (that also begs the question, how did this unit get tested with bent pins?).. right out of the box.. it's going to be returned. The China Reman clearly had a new connector assembly, and back cover... It's sad days when the China unit is quality and the USA unit is crap.. really sad days.. In the meantime, now that I'm back.. I'll be getting to the rest of this, pending the replacement second alternator.. sadly hoping its a China unit, since the USA remans seem to be poorly done.
 
I now have the assortment of parts and will begin install next week. The upper radiator hose is going to require some creative work to get it clear. I have the recommended driver circuit to mimic the ECU output to drive the second alternator, as well as switches so I can change modes from Dual to single and select either alternator. I also got the second alternator, both USA REMY Reman units were bad, and now have 2 REMY China units, one installed and working flawlessly. Pretty sad days when one gets the quality unit from China..
 
Aside from the grid heater what electrical loads do you have than need more than 220A?

The dual alternator option is great for people with high electrical loads such as winches, inverters, etc.

Even the 136A alternator is more than enough for 99.9% of users. 136A is a LOT of power. The 220A alternators will last longer pushing 100A than a 136A one will. Even grid heaters aren't that hard on 136A alternators, bad batteries are the hardest on them and would be on a 220A setup too.

I ask because I looked into it a while ago and determined it's not practical to install dual alternators with a 3rd gen.
 
Aside from the grid heater what electrical loads do you have than need more than 220A?

The dual alternator option is great for people with high electrical loads such as winches, inverters, etc.

Even the 136A alternator is more than enough for 99.9% of users. 136A is a LOT of power. The 220A alternators will last longer pushing 100A than a 136A one will. Even grid heaters aren't that hard on 136A alternators, bad batteries are the hardest on them and would be on a 220A setup too.

I ask because I looked into it a while ago and determined it's not practical to install dual alternators with a 3rd gen.
Thanks for the input. I do plan an inverter, have one in the RV, second try.. first was garbage.. Never do an MSW (modified sine wave).
I'm not so sure 136A is really adequate, my 1996 Saturn has a 140 amp alternator, as do both my Chevy Cruze Diesel cars.. none having an electrical load even close to that of the grid heaters. It's true the batteries take the hit on the grid heaters, especially with the 136A. The current 220A is much, much better, and is plenty for most people.
It's true, it's not going to be easy, but I hope to find a way and will post information to assist others willing to try, the new trucks are far too expensive for me to consider that option!
 
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That's got to be one heck of an inverter! My 1500w continuous/3000w surge inverter has a 150A fuse on it and runs anything I need except the AC.

I've actually had great luck with modified sine inverters, but it depends on what you're trying to run with them.

I too like being able to camp generator free, but I'd rather run a generator than idle the pickup.

Are you planning to use the pickup and inverter as your main source of AC while camping?
 
That's got to be one heck of an inverter! My 1500w continuous/3000w surge inverter has a 150A fuse on it and runs anything I need except the AC.

I've actually had great luck with modified sine inverters, but it depends on what you're trying to run with them.

I too like being able to camp generator free, but I'd rather run a generator than idle the pickup.

Are you planning to use the pickup and inverter as your main source of AC while camping?



The one in my RV now is rated for 3000W continuous, and 6000W surge.. it will start the A/C, but doesn't like to.. it typically beeps, shuts down... but comes back and the A/C is then running.. must be enough to get the compressor motor moving... but I try not to use it for the A/C.. it gets a 500A Fuse. I'd like to keep that inverter on during travel, and the Fridge on electric, to save propane, an minimize RV fridge fire risk.. mine had a recall where the put in additional sheet metal to contain a possible fire, but nothing to mitigate the risk of a leak and a flammable gas leaking out with an open flame.. That electric draw is about 330Watt, and that ends up needing about 30-40Amps DC from the batteries to run, and the trailer plug from the truck has too much voltage drop to keep up, it ALMOST does, but if the batteries on the RV still need a charge.. well not happening. I plan to add a heavy gauge winch type connector to solve this issue. I don't plan running the truck in place of a generator, the battery bank on the RV can handle it for a time, I'll be adding 90W solar to charge when off the grid, and I have a small 800W gas generator for charging when needed. Mostly the truck upgrade is to ensure I have plenty of power in travel mode.. and since it is possible to run A/C on my inverter.. open that up when it get really hot... with the dual alternators, it could run that. Also, I would like to add a Truck inverter, similar to what the RV has. It was fairly inexpensive, from amazon.com.. and that unit has proven to work well, a pure sine unit. The bad unit was a Modified Sine, 2500/5000 peak, Duracell (Xantrex) so should have been a quality unit, it never worked well from day one. It could barely run the microwave, and nearly caused a fire with a cordless drill battery charger overheat, that problem is apparently common with MSW inverters. Also the voltage drop with load was substantial, even the 300 watt fridge brought the AC voltage below 100Volts RMS.. The last straw that made replacement a must, it would periodically restart, under any load condition, and the Xantrex tech support had no ideas to correct issue... the pure sine doesn't go that low with 3000 watts on it, I've tested it. It is night and day difference. Also, it's some off brand China inverter that had good Amazon reviews.. ironically. I've also put in a smaller 12V power supply, and can turn off the original 950W converter, so I can use the small generator to supplement the batteries/charge and run any load when camping.. only a really high temperatures with A/C load would create a problem with this set up. It allows me to keep the 2400 watt, 75lb Generator at home and take the 20lb 800 watt unit, which is also very quiet and efficient.
Here is the inverter I used in the RV: https://smile.amazon.com/gp/product/B0131PZ9J2/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
 
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Just wondering if you ever thought of a truck mounted PTO generator. Such as these. http://realacpower.com/



YES, actually I have. If I still had the Duramax with Allison, I'd likely have one. They don't have a configuration for the Dodge Ram with 4X4, I did consider my own fabrication on that, a PTO with a 4 pole generator head.. but very complicated and the drive shaft path is just not an easy problem to solve, the transfer case is in about the worst possible place to make it near impossible to get from the PTO to where the genset could mount. The other side would need major exhaust system work, then heat shields, etc. The disadvantage to the PTO generator would be all that, plus it would be of no use while in travel mode to support additional loads, the advantage to the dual alternator/inverter is that it can produce power in any mode, parked or travel. The new inverters are much more efficient and reliable than they used to be.. and cheaper.
 
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