I am not saying that the radiator is not the problem, but if the thermostat is not opening, and it is not being by-passed, how is having a radiator that is too large causing his problem?
It's because I don't believe it's the problem. I may very well be wrong.
Regardless this mystery will go unsolved. I currently live 5000km's away from where the truck is kept and was back home on vacation for 3 weeks. Thought I could figure it out in that time. The truck broke down on me today (ignition issues) I'm Flying back home to bc tomorrow . It will have to wait until I have another chance to work on it.
Thanks again for everyones input. Sorry there was no happy ending yet.