'18 6.7L Diesel alternator?

[horsemare]

What size, how many Amp's etc? Took it to a mechanic and he tested the batteries, it said both batteries were shot. I replaced both batteries and it still wouldn't start. I went to auto zone and they asked me if it had dual alternator, I said there is only one. He asked if I needed the high voltage? I was thinking yes because it pulls my 4 horse gooseneck. I got in this morning and it wouldn't start. Should I have gotten the lower voltage?

 

[Tach_tech]

If you put 2 brand new batteries in and it still doesn’t start, the alternator has nothing to do with that. Does it crank when you try to start it?

 

[horsemare]

No but if I put the battery charger on it will crank over

 

[Tach_tech]

Did it crank after you put the new batteries in it? If it did but doesn’t start, do you have access to a scan tool to check for any codes?

 

[mtnrider]

Have the new batteries load tested... sounds like you still have a battery issue. It is Not your alternator.

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