My sister has an 02 Chevy 2500 that recently became difficult to start. It doesn't matter if it's hot or cold, she has to cycle the glow plug light several times over before it will start, and even then she will have to crank it over numerous times before it will start. She took it back to Chevy they told her it was the batteries. They put in two new batteries, that helped for a couple of days, but it's back to being hard to start again. She can change the fuel filter and it will start fine for a day or so, then it will go back to being hard to start???? Anybody else ever come across this. I've got a cummins, don't know much about the duramax. Derek.
