2006 LBZ charging issues

[BowTieDmax]

Ive had a 2006 D/A for about 2 years now. This was a salvage rebuild that I did. Ive done alot of rebuilds and have done all very well. This truck was not bad at all and only had 36,000 miles on it (now has 43,000). I put a new frame under it because it folded at the right front wheel. Nothing got to the motor at all. It needed the outer part of the airfilter box and a cooling package.
Well my problem is that the charging system is always low. When you start it will be around 11-13 volts and after a while it will maybe come up to 13-14. But if you put the windows up and hold the buttons longer after they are up it will pull back down to 11-12volts. I had the alt and batteries checked. If you start the truck cold then in about 2 minutes the alt. will be too hot to touch, so I know its got a load.
I talked to John Kennedy last week because of a vane positioner issue and he thought that the 2006 had a issue with the glow plugs not shutting off. He said that there was a need for a updated reflash from the dealer to fix. Well I took it to the dealer last week so they could relearn the new vane positioner and they reflashed everything. They said the charging seemed better. I went on a trip this weekend pulling a 35 toyhauler and I was 14-15 volts. All seemed better. MPG was at 12-14. I started the truck to come home and the charging system was down again and mpg was 6-8mpg. i do have a check engine light that came on Thursday night and I will look at it tonight when I get home from work.
Last week when my buddy had the tech 2 hooked up trouble shooting the vane positioner I did notice that the glow plugs were still on and pulling 17.5 volts. I quess Im looking for direction from anyone so when we borrow the tech 2 again we can focus in the right direction.
This is my 4th D/A and still have a 2005 as my main truck. This truck just sits in the garage unless I make a trip. This is why I havent had to worry about to much. But I am concerned after hearing about the glow plugs staying on and burning off the tips.
Sorry so long but just trying to detail as much as I can.
Thanks,
Paul

[Kennedy]

The engine will start and run fine with no glow so I'd temporarily disable the system. I don't recall the nature of teh recall, but it may have required reprogramming the GPCM

Also if you have your defective vane position sensor and have no use for it I am starting to collect them to see if we can analyze the common failure mode(s).


On edit: Document ID# 1797239

[TJNE]

I have a similar issue,(2007 LBZ) when I start it the voltage is about 11-12 volts after a 1-2 min it will come up to 14+ volts. I dont think the glow plugs have anything to do with it, Im in FL and have a heat index over 100deg and the glow plug light wont come on until probably Dec. I've had the batteries and Alt checked, any thoughts?

[JohnC]

I dont think the glow plugs have anything to do with it,

Actually, more likely the intake air heater. It doesn't trigger the dash lamp, but it comes on and off quite a bit in the first minute or two of operation.