2007 Freightliner Columbia with Detroit overheating soon as I start driving

Hey everyone, sorry for the long post but I hope I can get some answers since am broken and desperate on and on the side of the road.

A little background, the truck is a 2007 Freightliner Columbia with a Detroit 60 series. Had the head gasket and water pump replaced about 1.5yrs ago, since we notices pressure building up in the cooling system, overheating and causing water to spill out of the overflow tank but that did not help. I was running out of cash and parked it for a while. Then a family friend of mine borrowed the truck a few months ago and replace the radiator and the truck ran great with no overheating issue, until about a month ago when a new drive picked up the truck, it started overheating again and coolant spilled out of the overflow tank. Since I was low on cash, I talked to a mechanic who suggested that it could be air compressor head gasket leaking pressure into the cooling system. He suggested to have the driver remove one of the O rings from the reservoir cap, to ease up on the pressure build because a roadside mechanic said he maesurd about 60psi in the cooling system once he hooked up the pressure test guage to the reservoir while truck was running. It ran fine from the West coast to the east coast with a little leak on the overflow hose and without overheating, so long as the driver added water. He used about 2 gallons a day on his way back to the east coast where I live.( I know it sutupid but the idea was to have the truck back to my regular mechanic.)

Yesterday he picked me up on his way to get the load delivered so we could get the truck to the shop and have the air compressor changed while having the truck looked over. On our way to deliver the load, we parked for about 2 hrs only to be woken up by the a/c blowing heat, but the truck was not overheating, we started rolling down the road and within 5 minutes, temperature spiked past 225 and the truck shut off. We thought we were low on coolant so we added a few gallons of water, and waited till temperature dropped before we start rolling to the truck stop to get more water just in case. 2 minutes after we got back on the road, the temperature went past 225 again and the truck shut off again. We added more water and let it cool down a bit, then idled it for about 45 minutes to make sure the fan kicks in and its not overheating all was good, but soon as we started driving, the temperature went up to 225 again and truck shut off. It did this 4 more times. The weird thing is it'll idle all day without overheating and the fans kicking in as it's supposed to, but soon as we start driving, the temperature will shoot up past 225 after about 45 seconds and the truck shuts off.

Today I changed the 2 thermostats, but it's still doing the same thing.
I checked to see if there was any blockage to the radiator which is less that 6 months old, the radiator was flowing fine. When I pulled out the thermostat housing I turned on the truck and after it got to temperature, hot water started flowing from the engine block so that kind of confirmed to me that there is no blockage in the ingine. Something else I observed is that I have no heat flowing from the vents. I can't even get it to the mechanic because it keeps doing the same thing. Any advice would be appreciated.

 

Had water pump changed today. The impeller on the old water pump had rusted to the point where it was disconnected from the shaft. That explains why truck idled all day without overheating, but soon as I started driving, temperature would shoot up past 200 and cut off in less than a minute, due to the coolant not being able to circulate. Truck runs great without overheating even with a heavy load. Going to add thermocure to eat up all the rust, then flush with distilled water and add coolant.

 

The last driver that drove it had ran tap water before and after water pump. Part of it was my fault since I never did a coolant flush, but now am learning the hard way. But yes, the amount of corrosion in the cooling system would make you think I was running sea water.