So two things happened today... Truck ran fine on the hour drive to my friends house no problems what so ever. 4 hours later I start it, sounded kinda weak, but I didn't wait for the "wait to start" to go off, so I didn't think anything of it... I'm driving in town abour 40 mph and my engine temp skyrockets at a light almosted pegging the needle, start driving drops but stays above 190* Right after that my voltmeter drops half way between 0 and 14 then keeps jumping back and forth. As of right now everything is back to normal and the truck runs just fine. Maybe just a fluke? Something else?

As for the engine overheating, I'm thinking the thermostat decided to take a dump because it wasn't boiling and my overflow resivior was empty.
As for the voltmeter I'm stumped... The alternator is good, I think I'm just loosing a battery. According to my battery charger, my passenger battery was fully charged but my driver side battery was almost dead.

 

check you batterys see what the cca are take them to auto zone and see make sure the connections are tight see if the cross over wire that hooks them together is good

 

Pull the radiator cap after it cooled off and see how low the radiator is.

 

sounds like could be a battery going I would check for a spot where something could have ground out for a second or just check the connections to make sure they are tight.

as for over heating like what was said before I would check coolant levels.

 

Also have seen this happen due to a bad battery cable....

The one to look at is the one which goes from the left battery down to the starter.Its held in place by a couple of straps and the oil pan bolts.When the insulation wears or breaks the cable will short out on the pan rail and cause symptom like you just seen.....Andy

 

Okay I finally got some time to go through and look at the possible problems. All of the wiring looks good, the cables are all in good condition and seated on the battery terminals. As for the radiator, its full so I'm still stuck on the overheating problem.

Once I checked everything, I took it for a drive, my engine temp was slilghtly above 190 which is abnormal considering it usually stays about 160*. As for the voltmeter it stopped jumping around, but before it sat a little above the halfway mark, now its dead center on the half way mark. I'm thinking of replacing the batteries and going from there...

Also when I got back from my cruise, I had the hood up with it running and their was a little puff of smoke from the back of the engine on the passenger side, I'm praying its just an exhaust leak from the elbow off the turbo but I'm dead sure its from the engine so I'm thinking blown head gasket which would explain my engine running hot right?