I recently purchased a 07 1500 quad cab 5.7 hemi with a 8' bed, that will not start when it's hot . I turn the key and i get a single crank thud and nothing , have to sit and wait for it to cool off before it will start again. I replaced the starter and battery already and to no avail and I really don't want to go down the rabbit hole with this just looking for a straight answer of what this problem really is and how to correct it . And also when I shut down the engine , I also hear what i can only describe as an electrical arc dissipating (think of one of them tesla globes in the science store) a few seconds after the engine is off , is it related or something else entirely . Hoping someone else out there had this issue and resolved it.. thanks..

 

Is it the starter solenoid that makes the 'thud'?

 

No it kinda sounds more like in front off me rather then underneath , like the engine it self wont crank

 

Now i did hear about these hemi's not having a strong enough starter in it and they have the possibility of getting static electro stopped . And i should get a beefier starter like a racing starter . But im really trying to confirm this before i start throwing more money around

 

Do a starter draw test. Have the engine good and hot, and then test.... See what amp draw looks like.... Also, try pulling the serpentine belt, and trying again when it won't crank...... might be a pulley seizing up when hot, and preventing the starter from turning the engine.