I started the truck a few days ago and noticed a lot of white smoke coming from the exhaust. Took off exhaust pipe at the turbo and started it it up again. Coolant and white smoke came pouring out. I shut the truck off and checked the dipstick. It was very full and very milky so coolant is getting into the engine. I dropped the oil pan and pressurized the coolant system and noticed coolant coming out of the 5th cylinder. I noticed dripping from the inside of the piston sleeve. It came down the piston and dripped off the wrist pin. It looked like the sleeve was fine with no visible cracks. I took the exhaust manifold off and looked into the exhaust port of the 5th cylinder, It was full of coolant. I noticed a tiny bit of what looks like maybe copper in the exhaust port. My guess is either a blown head gasket, or maybe an injector cup? I know the injector cups are copper. I personally drive this truck every day and I know for a fact it never even got close to overheating. Even with coolant coming out of the turbo it started right up and idled normally. After letting the truck sit overnight i tried to start it one more time to get a quick video but the motor was locked due to the cylinder being full of coolant i assume. I didn't keep trying to crank it out of fear of breaking something. So has anyone had this issue? Would you say an injector cup? blown head gasket? cracked head? The only Check Engine Light Code that came on was low coolant in the reservoir.