I have an 04 LB7 that I've replaced headgaskets on along with replacing and sealing all injector cups. It is no longer puking coolant but the upper radiator hose is still hard. The glow plugs were pulled and there is no coolant in the cylinders so the cups are fine. The overflow cap has been replaced along with the thermostats. It had dexcool in it but was drained and replaced with standard green coolant while the truck was being worked on as it was constantly puking. The radiator is flowing 60% due to some damaged fins. What else could be causing a hard hose without the puking?