I will do my best to assist you. When you are finished please click on accept only if you are satisified. I don't get paid unless you do.Please do not accept if you cannot leave positive feedback. I don't know if you are a tech or a just working on your own vehicle so we may have to fine tune the answer. I only know as much about your problem as you have told me in your post, so my answers will be based on what you tell me so please add all the details you can.
What is the 8th digit of your VIN?
What is the 8th digit of the VIN please.
Ok, does it fully overheat or does it push more coolant out than anything?
Ok, Does the engine coolant pressurize very quickly?
Don't know. do you want me to go start the truck and time it?
OK, is the check engine light on?
Ok, I suspect that there is either some debris between the rad and the charge air cooler or the head gaskets are leaking.
Usually not. THe compression or even the block test usually do not. However if it always pushes the coolant out of the tank and hose, and you have changed the thermostats and pump, then that is all that is left.
There is a GM Service Bulletin dated August 2006 that I think refers to this question. Bulletin # XXXXX XXXXX Do you have an opinion on this as a possible resolution to the problem we are encountering?
The truck goes back to the shop tomorrow. Anything (other than the previous conversation) we should ask/share with the technician?
IF it was only towing, then maybe, but since it overheats without towing I would say no. Possible that it was the cause and the overheating caused head gasket issues.
My pleasure. You can reply at any time for follow up information regarding this issue, even after you accept my answer and I will reply.
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