So truck was blowing coolant out of the reservoir. Took it to the dealer, dealer said head gasket was blown. We had the dealer fix it, and put in ARP 425's. Also checked the head for flatness- not warped at all. Pulled the trailer back to Wisconsin, half way home, truck was doing the same thing. Took it to the dealer in Wisconsin, they tested the truck, said the gasket was fine, and not leaking. Changed the radiator cap, and sent me home with paperwork saying the head gasket was good. I pulled the truck in the garage, and checked the studs personally. Two studs we're slightly under-torked. I ran them all up to 135ft/lbs, and doulble checked them again.

So 3 weeks later i'm back on the way to Idaho, and surprise, truck is overheating, and again coolant is all over the engine, coming from the reservior. This is after 1600 miles of flawless running in heavy wind, pulling the trailer. It was just like some one flipped a switch.

So now what do I do? And where do I start? I have no idea why the truck is blowing coolant out. I was thinking maybe cracked head possilby? It would be a long shot, but this one is a head scratcher. The oil is perfect, no water in it.

Truck has been fully deleted, no egr or cooler. No cat's, or Dpfs. I run the smarty. First trip home I ran on 5. This trip home i ran on 7, and I have a pyro and boost guage. Any ideas?

 

I have truck I'm working on right now with same issue. The EGR cooler went out engine overheated. Replaced EGR cooler same problem, blowing coolant out and overheating. Pulled the head and is cracked and cylinder walls are scored. New engine time, I'll take a few pictures tomorrow, I'm pulling the cab to install complete reman since it still under warranty Did you have head magnafluxed and pressure tested?

 

Might also check to see how soft the lower radiator hose is. I've had a couple of different rigs come into the shop with the same symptom over the years and it turned out that during extended highway driving, the lower hose was collapsing and causing the same symptom.
As stated above, I've also seen cracked heads cause it also.
Good luck.

 

Head was not magna fluxed, at just over 70k, I never even thought to check it. Also did not check the lower rad hose, but I will mention it to the dealer. The thought of a cracked head is not good news since (of course) it is out of warranty.

 

If dealership would have done it right the first time and sent the head out, and had it decked you wouldn't have had this problem a second time. Did you ask them how they checked the head for "flatness"? My guess is they will come up with some bullshzt excuses and you'll be paying for the redo.

 

I have same problem took it to dealer they said thermostat so I changed it.No help then they said radiator cap so I changed it no help. Beyond towing it also does it if Iam cruzing around in the mountains. Small inclines creates higher rpms and no speed for air I guess. So is the only way to check for cracks is take it to a dealer or is there some tests I could possible do?What would cause a crack? Since I did a complete delete I haven't had any issues at all for two years. I tow easy but always keep an eye on my gauges and its never been above 210. So it must be able to crack without mixing fluids that are visual? Any info would be great Thanks