My wife was towing our horse trailer with our '05 3500 hemi when she noticed it didn't seem to be shifting correctly - either a too low gear or a too high one. About a half mile later, all the dash lights flashed and it died, at about 60mph.
She tried to start it again but it acted like a dead battery, clicking with no crank, or an extremely sluggish crank.
I pulled the alternator and battery and had them tested at the local parts store. The alternator tested good, but the battery was at 12.2v and only 49% charged.
When they attempted to charge the battery, it failed to take a charge and tested bad. I bought a new battery and installed it. The truck started for about 45 seconds and then died. The first couple of tries where sluggish cranks or just clicking. Now it doesn't crank at all. My code reader didn't pull any codes.
Specs:
2005, Ram 3500, 5.7l hemi, automatic, DRW, 195k, 2WD, 4D, basic Work Truck model (manual widows and doors, no remote, but does have A/C and radio).
Only aftermarket modification is a 160° thermostat.

Need some help, as I'm not sure where to go next.
Thanks

 

Is there a high current draw during the slow crank? (do the battery cables get hot?) How does the oil look? Think if the starter tests ok, I would start looking at the various grounds.

 

Oil's good (changed not that long ago). Will have to check the current draw tomorrow. The slow crank (when it cracks at all - mostly it doesn't even do that) only lasts a second or two.
I'm wondering if the ECM/PCM -not sure which one it has?- might not be fried.

 

I am not sure the pcm is even involved in cranking.... but, given that even friggin' power windows are now controlled by a computer..... it's anyones guess. When it doesn't crank, so you hear a click from the starter relay in the TIPM? Does the starter solenoid thump?

 

When it's doesn't crank, sometimes it clicks like a low battery, but more often it just "chugs" a single time and then nothing.
After it sat while I pulled the alternator and battery, it started and ran for maybe 30 seconds before dying. It also started when jumped (before the alternator test and battery replacement), but stalled as soon as the RPMs dropped. It went immediately back to not really cranking. That's why I initially thought alternator and was surprised when the alternator tested good and a brand new battery didn't result in it cranking reliably.

 

I rec starting with trouble shooting that will either fix the problem or confirm that the basics are good.
Heyyou's comment on current draw during start is great idea. A failing starter could be killing your battery. Your battery should read at least 12.6V static, and should not drop below 10V during start.
There are good videos for checking battery grounds. Important to understand that your starter, and many other elec systems, are grounded to the engine. Heyyou is once again on target with recommendation to check grounds.
Stalling could be result of bad grounds, could also be result of starter not disengaging flywheel. Many other causes for stalling, but your symptoms point to starter and/or grounds.
I rec get a voltage reader that plugs into your cigar lighter. The kind with digital voltage readout and also charges USB. See if voltage fluctuates with truck running.

 

Thank you everyone for your help.
Here's where I'm at this afternoon:
I tried starting the truck again this morning. It attempted to turn with a real sluggish crank once or twice, then nothing.
I plugged in one of those 12v USB charges things that also displays the voltage. it read 11.9v static, but dropped down to ~6.9v - 6.7v when I tried to crank it (again with no response to turning the key). I noticed both the negative cable and the started itself were both very warm to the touch.
I put a charger on the battery and pulled all the wires from the battery. I cleaned every post, nut, bolt, and mating surface at every point (negative at battery, negative at body, negative at frame, negative at engine, positive at battery, positive at starter, and positive at fuse box terminal).
I ohmed out every battery wire (positive and negative sides) individually and none had a resistance higher than 000.1 on my Fluke.
I pulled the starter and had it tested. It test just fine at the parts store bench.
Once the battery was up to ~12.2v - 12.3v according to the little USB thing, I tried starting it again.
Once again the USB reported a drop to ~6.7v, and no crank (or clicking, either).
Based on the advice here, I'm thinking there is a ground somewhere, but I didn't see anything with a visual inspection of the battery wiring harnesses.
Any help on what might be the best place to start hunting a ground with these symptoms would be greatly appreciated...or a specific resource on how to tackle this in a methodical manner?

Thanks again to everyone's who's provided help so far.

P.S., also no crank/click when the charger was hooked up on a 30A boost cycle.

 

If voltage drops that low when you turn the key, the battery is bad, or the engine is placing an excessive load on the starter..... Pull the serpentine belt off, try and crank the motor again, does it spin any faster?

 

Shallow cycle batteries with 11.9V readings are usually unrecoverable and need to be replaced. 12.2V is too low to determine if the starter working properly.
Additional areas to check:
- parasitic draw on the battery
- get second check of starter and alternator
- check the ground of your fuel pump. I believe your pump is grounded to the frame and should be easy to access.
- what is battery voltage with truck running? Should be at least 13.5V.
- What do the terminal ends of the grounding cable look like? Do you see some green corrosion? Is the cable flexible?
Are you using a multimeter/DVOM for these checks? A probe tool is really handy for troubleshooting electrical problems.

 

Hello everyone, sorry for the delay in responding.
I now think the motor is seized. I removed the serpentine belt as suggested above, but did not have any change. It still would not crank - at all. So I tried cranking it by hand and couldn't budge the flywheel in either direction. I took out half the sparkplugs all on the driver's sides (before ending due to weather) as was still unable to move the flywheel.
The next day I towed it into the barn, pulling it back about 75 feet and then pulling it forward about 30 feet. I left the auto transmission in reverse when backing and put it in drive while pulling it forward, hoping it would rotate the engine (I don't know if this is a correct assumption). I had marked the flywheel, and from what I can tell, it did not move. I will finish removing the remaining spark plugs and try to rotate the engine by hand.
If I still can't budge it, am I correct in assuming the engine is seized?

Thanks again for the help.

P.S., in case there is some confusion, the truck will currently not start and it does not crank at all. I appreciate the suggestions about the voltage on the battery, but I can't give an answer on cranking or running voltages. I have tried to crank the engine using a battery booster, but as of now, still no crank (and no click). That's why I'm afraid the engine is seized. I would really love the be wrong about that, though.