DuraMax alternator?

[EVIL X]

My '02 2500HD DuraMax has had an odd alternator issue since I bought it new in July 2002. At start-up the alt. gage takes approx. 1 minute to indicate full operation(14+from <12 VDC). The truck is now 5 yrs. old w/60k mi. It seems to have developed a new quirk in addition to the original one. Now even after full op. of the alt. the lights flicker noticeably for an add'l. minute. The belt has <10k mi. on it and is the correct length and tension. Is my alt. going to leave me stranded?

[DmaxMaverick]

It's getting colder, and the longer glow plug and intake heater cycle will cause that. If it's worse now than it's been in past winters, I'd suspect a poor connection somewhere. 5 years isn't too soon to have connection problems, especially if you are around salt in the winter. The voltage regulation is controlled by the PCM.

[cowboywildbill]

Also, How are your battery's ?

[BvilleRay]

My daughter has a 2002 D/A GMC. She said the truck was failing to start at times. I checked the battery cable connections and found corrosion at the battery end. An old toothbrush and some baking soda water solutionn was used to clean the positive cable ends. CAUTION, only disconnect one battery at a time. If you disconnect both batteries at the same time for over one half hour a SES light will come on. The code was defective battery. If you have a voltmeter check the voltage at the batteries with the engine running. You should have at least 13.8 volts.
Now turn on the heater, lights and radio. If the alternator is good the voltage should be the same.

[Hook_'em_Horns!]

The alt delay on the DM is doing what it's designed to do. Doesn't have instant full charge like the gassers.

[DmaxMaverick]

Exactly!!

And, gassers don't have glow plugs, intake heaters, or 17+:1 compression.

What was the question?

Oh, yeah.... With the Duramax, charging should resume up to the PCM set VR as soon as the glow plugs and heater shut off, and the batteries recover from the spontaneous drain. Other than that, you're exactly right.

[dmaxster]

on my truck I had gotten only 3 years on my batteries, 70,000 miles on them. I just replaced the alternator on my truck last summer, 140,000 Miles on that approximately.
Can't complain, I have 187,000 Miles on it now, No Major Major problems.

Just the usual Injectors.