Truck Overheating

[fast 99]

Typically when it’s overheating and i go to shut it off, it sputters for about five seconds or so after i’ve shut it off. I’m pretty sure it actually overheating because of what i just mentioned and the smoking once the gauge reads much past 3/4ths

Factory gauges are indicators and can't be relied on for diagnostic purposes. Mechanical aftermarket gauges are reliable, hint.

As I said before, if not pushing water out it's likely not as hot as you think. Immediately after shut down engine will hot soak. Coolant temp will rise, sometimes 20 degrees. If near or overheating coolant will boil.

Dieseling has many causes. Any motor will be more prone to doing it when hot. Really need to get accurate temp readings.

 

[RandyE]

I had this same problem. Turned out it was my rad. I could see a white substance at the end of some of the tubes. I thought it was calcium buildup from poor water. I talked to a rad shop and he explained it was called solder bloom. He figured some of the tubes would be plugged with it. He could clean it but almost guaranteed it would leak. I replaced the rad and it works fine now. Worked for me anyway