Ok sounds easy my 99 2500 CTD is getting harder to start the last few weeks. Even after driving still hard. Alternator is charging. I replaced my Duralast golds that were 2 yrs old and tested bad so I thought sweet easy fix. (Warranty's can be great) I have not tested the new batteries but the characteristics are the same and now almost no start. Can it be the starter? Still stock with 105000 miles. Any help is appreciated. Thanks

 

With what you describe, it kind of sounds like your starter may be getting weak. Once the truck is running, does it run strong? When you say its not temp related, do you mean outside temp or engine temp?

 

Runs great once started. Even when engine is warm still cranks hard. With new batteries I guess the starter is the next place to look??

 

It does sound like the starter, just pop it off and see if you can get someone to take you to a parts store to test it just to make sure. Although it isn't that uncommon for brand new batteries to be bad right off the shelf, you would probably not have hard start issues when the truck was warm if it was just them.

 

Yep was the starter. Took it to parts store and had it tested and passed perfectly 4 TIMES. I said under a load could be different so I gambled and bought the new one. Works great. Its hard to ignore the computer screen sometimes though. Thanks all.