cant start

[ClaytonG]

Just did head gaskets studs, egr delete. Was running great for a couple days then it ran the batteries down to nothing and had to be towed. Now it wont even try to start. I just replaced both batteries. it has the swamps 58v hot ficm. no cat or muffler. 2003.5 excursion 6.0 PLEASE HELP

[NYC F-350]

Sounds like a dead alternator

[ClaytonG]

Alt tested good.

[dannyboy950]

Check out the starter make shure ya didn't fry it. What is the volt/amp draw down when ya try to crank.

[ClaytonG]

dont think its the starter. It cranks with no problem. Should i have the alternater tested again? Really at a loss with this! it was running better than ever then it just died. I cant find anything wrong. I just spent 3k on all this and

[NYC F-350]

Pull the IPR and have a look at the screen on the end of it.
Your description of what is happening is seriously lacking detail. Explain exactly what it is/is not doing, what year, any modifications done to the engine/truck.