I'm seriously considering replacing both alternators on my dual alt 7.3L now, before they fail. When did Noah build the Ark? Before the rain. The OEM 6G small frame alternators have historically proven to last less than a lifetime, so I'm investigating other types of alternator guts that are still available in a Ford T mount frame.

Most of the options I'm considering only offer a two year warranty. But for some reason, I think that these options still might be more reliable than the lifetime warranty offered by the chain stores. The true cost of a replacement alternator is the downtime and inconvenience of failure, which can often exceed the cost of the alternator itself by several times, depending on where you are and what you are doing when it fails.

 

Looking past the red bling, through the vent holes, and at the stator windings themselves, this alternator is better due to the wire shape, which permits more copper to fit in the same amount of space. Where traditional alternators have 36 slot windings, this style alternator has 96 slot windings. The rectangular wire shape stacks tighter together, reducing the air gaps inherent in traditional round wire windings, resulting in a higher density of copper, in more slots, in the same (or smaller) circumference.


This is called the segmented conductor design. It was invented by Denso, introduced in some Japanese cars in 2000, spread like wildfire world wide, and recently Denso celebrated delivering their 100 millionth segmented conductor alternator to OEMs. Ford is one such OEM, and when Ford incorporated the Denso design into the 2008 6.4L diesel Super Duty, this enabled aftermarket rebuilders like DC Power Inc to have a "frame" to work with that bolts into Ford truck vehicles. (Now DC Power has their own drive end frames machined out of aluminum billet in bulk, but other vendors still use the cast frames that are identical to the OEM 6.4L alternators.)


This is also why Nsaan was able to easily bolt up a 6.4L alternator to his 7.3L. In fact, the 6.4L alternator, at 200 amps, is 10mm in diameter SMALLER than the large 6G case 6.0L alternator, at 140 amps. Again, this is due to the inherent efficiency incorporated into the Denso Segmented Conductor innovation. The problem Nsaan had is that he used the 6.4L alternator straight off the shelf, without realizing at first that by the time Ford began using Denso alternators, Ford had also changed charging voltage regulator control to being PCM based.


It is NOT a matter of just swapping regulators to a "gray/gray" color... because the Denso regulators are a completely different design, as is the bridge rectifier that the regulator connects to. We can easily swap regulators from 6G to 6G, but not from 6G to a Denso. And this is where the alternator vendors like DC Power, Mechman, and boutique resellers like Nation's etc come in. The aftermarket alternator supplier industry from whom these venders purchase the products for resale from have already worked out which Denso IC regulators have chips that can function transparently to the simple way our old original alternators operate... internally regulated, needing only the lamp and sense circuits to work.


Not all DC Power Engineering "upgraded" or "high amp" alternators are of the Denso segmented conductor (aka hairpin, nicknamed after the way the flatwires nest tightly together like a bunch of hairpins in a Japanese bun) type. Here is a photo below of FTE member sledhead999's install of a DC Power Inc alternator that is NOT a Denso segmented conductor:





In this case, looking past the color of the housing (or lack thereof), and through the vent holes to the windings, we see round wires. This isn't a hair pin, so the kinds of upgrades DC Power did to this alternator may have been just to increase the amperage rating of the diodes... perhaps upgrading to Avalanche diodes. Perhaps welding the leads into the bridge rectifier plate instead of soldering them. Maybe using the HD version of the regulator. But this is no Denso.


At the same time, not all Denso alternators are segmented conductor style like LMM's powdercoated red one. So not only do we need to see beyond the "bling factor", we also need to look beyond the brand name, beyond the manufacture name, beyond the reseller claims, and beyond the amperage ratings to sort through the details of what we are paying for, once we step up to spending more than $200 to get something better than a cheap Chinese wax and oil store rebuild and replace.


I realize this was an old thread, but it was linked through a link to a thread today, and Springer Pop's question popped out at me, and opened the floodgate to some of the musings I've had about alternators lately.

 

That was a VERY comprehensive and detailed report!

New technology in the power production business.

It completely answered my question.

Thank YOU!

Pop

 

Great post, now how much for the alternator. Bought my son the 185 DC alternator for his 6.0 year or so ago.

 

Most new Denso flatwires (aka hairpin aka segmented conductor) with the correct regulators retrofitted for our application are priced above $500. I've not found one for less yet, but I'm still looking.

 

Any idea about whether that flat-conductor technology has trickled-down to the starter motor market yet?

Pop

 

Yes. 15 years ago. Back in 2001, when Denso introduced their Planetary Reduction Segment Conductor starter, aka the Denso PS line of starters. The "S" is for Segmented Conductor, which denotes the same rectangular conductor profile that I was discussing earlier for the Denso alternators, which were introduced a year prior.

I believe Ford starting using the Denso PS starters beginning in 2002. I still like my 3 bolt Mitsubishi starter. I wrapped a heat shield over the top of it years ago, to protect it from the passenger side exhaust manifold. Hasn't given me a lick of trouble yet, knock on flywheels.

 

All very good info above!

I have the same Mitsu starter that you do, and at a quarter-million miles, it's still going strong.

Pop