Frustrating problem. Truck turns over real slow when cold almost like a dead battery. This happens the first time I turn the key to the start position. If I turn the key back to the "off" position and then turn it right back to the start position it turns over real fast (normal) and starts. Batteries both load test fine and are fairly new. Yesterday it was a little colder and it didnt start on the second or third attempt and by that time the batteries were dead. I jumped it and it started right up. Sounds like a battery issue I know, but I had them load tested again this morning and they test good. Any thoughts?

 

I assume you made sure the terminal connections were tight. Check all the cables, especially the ground. After that I would take the starter off and take it in to have it tested.

did you take the batteries in to a parts store like napa or were they load tested by a cheap harbor freight type of tester. The cheap load testers can show good but they wont show if there is a bad cell in one of the batteries.

 

Battery connections are tight and batteries were tested at Advance Auto.

 

Before trying to start it the first time try rapping the starter with a hammer, then start it for the first time to see if it fires off fast. If so, may be the starter.

 

Will a bad starter really drag the batteries down that much? And only on the first attempt but typically not the second?

 

My first guess would be the starter then.
There may be a relay sticking. I don't have the book in front of me right now, but it should tell which one in your owners manual. You could swap a couple relays around to see if the problem persists. Or just buy one, they are fairly cheap.

 

Yes, when starters start going bad sometimes it's intermittent. Like lhud said, tapping on the starter sometimes will help it start.

 

Yes, the starter is actually part of the charging system. If all connections are good and tight, there is no corrosion in the cables themselves, and you have a good ground, it really does sound like it is the starter.

 

Ok I'll get going on that piece of the puzzle. Thanks guys!

 

I would bypass the starter relay on the inner fender a couple of cold morning starts to diagnose things, the relay contacts could be burnt to a point to cause this.

 

Got the new starter installed and all is well. Thanks for the help!

 

Thanks for reporting back.

 

Glad to hear it. Thanks.