So my 110 amp alternator is dead I think. only getting 11.2 VDC out of the red terminal on it. So I assume that means it's not happy. The idiot light came on yesterday on my way home and pretty much did not go out unless I was well past 2500 rpm.

It has come on in the past but after some highway driving always went away.

My loads on it don't seem to be that significant.

My Vegtherm around 25-30 amps
A1000 pump maybe 15-20 amps fused at 20

I always drive with the headlights on so what ever that load is and then what ever the truck need to operate.

Both batteries have red ***** in the normally green little windows.

It cranked very slowly this morning and finally started but I didn't think I should drive it any place since I think that was my last start till I can charge the batteries.

I'm a little worried the dealer may say my loads killed it. But, not sure.

I see I can get a replacement for about $200 I also see there is a 120 and 140 amp alternator for the trucks with duel alternators. I've also read it's a pain to change.

Can I put one of these larger alternators on a single alternator truck, since I assume the loads are what killed my last one.

 

I seriously dont see where your loads killed it, you have a 110 AMP alt, and your total loads 50 from you stated, and add another 5-10 amps for all the lights, thats only a 60 amp load, so that leaves another 50 amps to run varouis things like the ECU, charge the batteries, if you had the heater or A/C on, thats a load too,etc. but usually the first load the computer makes the alternator drop (i.e. stop appling charge) is the batteries, then it concentrates on the other loads.

someone with more experience should be along shortly to help and correct me... lol

 

Here's some info on the alternators - scroll down for the graphs.
http://www.fleet.ford.com/truckbbas/...df/05elect.pdf
You can see there isn't full rated output available at low rpms, not even close. Under 1500 rpms the output drops quickly. To get that much current at idle your drawing off the batteries. That by itself shouldn't kill the alternator, but done long enough I guess it could over stress it to fail as your batteries discharge. One thing I've seen alternator rebuilders do is use a slightly undersized pully on the alternator to keep it spinning faster. This will get you a few more amps at low rpms. I suggest you install an ammeter on the system to monitor it for charge-discharge rate. Then you can see in real time what's happening. Good luck.

 

Alternators need to be cool. If possible duct some air from infront directed at the unit. I did it very easily on my 96; still looking to do it on my 04..
Good luck

 

I wonder how those RMPS on Page 7 for the alternator relate to the engine RPMS. My engine RPM is normally 1850-2000 or less.

Lets see what the dealer tells me tomorrow.

 

Good point leskwvo. I was thinking engine rpm; they are showing alt. rpm. There may be a difference there.

 

There was not too big of a differance on the chart netfly posted between each end on the temp scale. Cooler is better for sure, but on the 6.0, as you know there is very little room for much of anything under the hood. The batteries get cooked under there also.

 

I doubt the cooling would do much good. Bolted to the motor its going to return to motor temp eventually. You'd be creating motor thermal cycling possibly and water in rain may not be the best thing on it.

 

Got the call today from the dealer. Bad alternator, repalced under warranty.

No questions asked about my WVO kit that is on the truck. I did peal the stickers off before I had it towed in though.

I pick it up in the morning. I has sucked driving a Handa CRV 4 banger for the last three days.