Our sons 1989 Chevy truck overheating

Can you see it leaking from the water pump or hoses or the heater core or radiator?

We just purchase the truck for him 3 months ago. We have put in a rebuilt transmission but now it's overheating

We can not see any leaks at all

Is there oil or foamy substance in the coolant reservoir?

It started overheating the day the transmission went bad and my sons grandfather had opened the radiator cap when it was hot and it spilled everywhere. Then he added water to it for our son to get home. Do you think this is the issue.

It soapy looking one time but now it's not Thank you for helping us

At jiffy lube they said it was soapy when they opened the radiator cap

Sounds like it might be a blown head gaskit

We just went out this morning and looked at the resovour and its empty

Make sure it's not leaking into the trans cooler, could have been why the trans went out. Check the trans fluid and make sure it isn't pepto bismal pink

On a simple note, have you changed the thermostat?

I also have a Chevy c1500 1989 and my truck constantly overheats. My boyfriend and I tried sealing a crack or small leak that he found on the radiator itself with jb weld and that seemed to fix the issue for a few weeks and then all of a sudden it started leaking again.. not sure why this happened the only thing I could think of was because the in weld eventually came off or it cracked or something along those lines.. we've been keeping it filled with water and don't go anywhere without at least 2 water jugs but we've yet to completely fix the leak. Just recently the truck started smoking when it would overheat, which never happened before.. my boyfriend and I initially thought it was just because we spilled oil when we added a free quarts of oil to the truck, and just assumed that it would stop smoking when the oil that was spilled eventually burned off.. except it hasn't stopped smoking when It overheats and it still smells like the smell of oil burning off from being spilled.. it's puzzling, and the only thing we can think of it coming from is possibly a head gasket? We really aren't sure.. the leak never came from our reservoir tank though, it always leaks straight from the radiator because when you add fluids directly to the radiator by removing the radiator cap (not the reservoir tank) and pouring the fluids directly Into the radiator you can physically see the fluids leaking out underneath of the truck as you're pouring fluids into the radiator, the whole radiator probably needs to just be replaced in order for the leaking to completely stop, however, I don't see that fixing the smoking when the truck is overheating issue.. any mechanics reading this have any suggestions/advice? It would be highly appreciated.. have a blessed day

my truck over heats and shuts down and when i look under the hood when it shuts down the engine coolant is bubbling and and steaming and it is really hot does any one know why that would be happening?